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The Plant Doctor Is in the House

Sun, 07/06/2014 - 12:00pm

A couple years ago, in early spring, I got the kind of call that puts a “plant doctor” like me on edge. “Come look at the roses right away,” someone said. In my 25 years at the Chicago Botanic Garden, no one has ever called me to say, “Hey, Tom, come look at the roses; they look great today!” I’m in charge of plant healthcare at the Garden, so when I pick up the phone, there’s usually a problem.

I got the call about the Krasberg Rose Garden following a string of very damp nights that meant trouble—a white fuzz had spread over all the roses. The fuzz was a destructive pathogen that produces mycelium, or fungal spores. It can happen pretty much overnight. We ended up managing the problem, but it was scary to start off a season like that. Roses are tricky, prone to a lot of diseases and insect problems. Our friends at the Missouri Botanical Garden lost all their roses to a virus called rose rosette disease. 

I don’t just get calls about diseases or pests such as the emerald ash borer. I get called to the Butterflies & Blooms exhibition if the staff is worried about a larva or to the Elizabeth Hubert Malott Japanese Garden if there’s a raccoon problem. I like to say that I’m sort of like a CSI detective when it comes to plants. If a plant is failing, I try to find out why and what it needs. I look at the buds, the stem, the trunk, the root flare, the soil, and the plant’s history over the years.

 Tom Tiddens poses with a cardboard coyote cutout, used to deter varmints from veg.

Tom Tiddens and a plant healthcare specialist’s best friend head out to play fetch.

I also work with the horticulturists on preventive care, including watering, pruning, weeding, and fertilizing. When I see a problem in the early stages, I’m very patient and tolerant. I like to see if Mother Nature might take care of it—maybe a hard rain will wash away any aphids or the ladybugs will get rid of the pests, for instance.

People ask me how I track the health of more than 2.6 million plants here. I have two great plant healthcare specialists who work with me, and I really rely on the horticulturists—they’re my eyes out in the field—and my volunteer team, which includes a lot of master gardeners. Every week, I give the volunteers a map and checklist marked with target plants and pests. So a typical volunteer assignment, for example, would be to check the spirea bushes in the Sensory Garden for aphids.

 Bagworms infect a pine.

From bagworms…

 Rust infects a fruit and leaf.

…to rust…



 Black spot infects rose foliage.

…to black spot on roses, Tom Tiddens treats them all.

The average home gardener doesn’t have to be so methodical. Gardening shouldn’t be a chore. I like to keep things simple at home. I don’t like weeding, and I avoid using a lot of perennials or groundcovers. I like having a nice woodchip mulch bed and a mulching lawnmower. It’s the same thing with fall leaves. Everyone bags up all the leaves. Nope. I raise my mulching lawnmower, and I just grind them into the lawn.

Register now for a certificate class with Tom Tiddens, plant health care supervisor and certified arborist. From July 21 to August 28, he will teach Plant Health 2 with Kathie Hayden, the Garden’s manager of plant information service.    

©2014 Chicago Botanic Garden and my.chicagobotanic.org

Praying Mantis “Children” in the Growing Garden

Wed, 07/02/2014 - 8:35am

One of our favorite insects at the Chicago Botanic Garden is the praying mantis. So we were very excited to obtain an egg case earlier this spring. We decided to keep it indoors so we could watch it hatch, and then release the newly hatched insects into the Garden.

 Preying mantid egg case on a twig.

About 100 praying mantises emerged from this ootheca and were released into the Grunsfeld Children’s Growing Garden.

A praying mantis egg case is called an ootheca (pronouned oh-uh-THEE-kuh). The plural is oothecae (oh-uh-THEE-see). The ootheca was produced by a female praying mantis last fall. She laid her eggs in this foam of protein that hardened around a stick and protected the eggs through the winter. The eggs usually hatch in mid-June to early July. The half-inch-long immature praying mantis nymphs resemble the adult, but they do not have wings. 

 Hundreds of baby mantids pour out of an egg case.

Colorless praying mantis nymphs emerge from the ootheca all at one time. During their first hour, they darken in color to blend in with their surroundings.

After our praying mantises hatched inside an insect cage, I discovered that a bed of false sunflower plants (Heliopsis helianthoides) in the Grunsfeld Children’s Growing Garden was infested with red aphids. I released the praying mantises, and the hungry babies immediately began to feed.

 Mantis nymphs on the head of a Rudbeckia flower covered with aphids.

At first, the praying mantis babies seemed a little bewildered by their new surroundings, but they quickly acclimated.

 Mantis nymph on a flower stem eyes aphids—a tasty meal.

This mantis held very still as it eyed its prey.

 A row of mantis nymphs on a leaf face a stem covered with red aphids.

These four little mantises lined up and stared at the aphids that would certainly become lunch soon.

It wasn’t exactly aphid carnage—much to the disappointment of our eighth grade Camp CBG helper, Joshua, who assisted me with the release—but the young predators did appear to enjoy their first meal.  

 Preying mantis on liatris bloom in August.

By the end of August, some of our little friends will be as big as this praying mantis (and just as hungry)!

It may surprise you to know that although it looked like a bad infestation, aphids are not really a big problem for the plants. When they are very abundant, it does not take long for natural predators like praying mantises and ladybugs to find them and move in for a feast. Predatory insects will take care of the problem if you are patient and let nature take its course. If aphids show up in your garden and they bother you, we recommend hosing them off with water rather than using an insecticide, because chances are pretty good that there are beneficial insects on your plants, too. Hosing with a strong jet of water will knock off all the bugs and kill most of the aphids, but it won’t be as devastating to the mantises or other beneficial insects as poison.

We have placed praying mantis oothecae in the Regenstein Fruit & Vegetable Garden and Elizabeth Hubert Malott Japanese Garden, as well as in the Children’s Growing Garden, to ensure that there will be a population of our favorite insect for you to find. Many of them will survive on aphids and other insects they capture and devour on our flowers, and they will grow up over the summer. The next time you visit, stop by and see if you can find them helping our plants remain healthy and less bothered by pests.

©2014 Chicago Botanic Garden and my.chicagobotanic.org

Today’s Harvest: Herbes de Provence

Tue, 07/01/2014 - 10:36am

Named for the countryside herbs growing in the hills of southern France, this Today’s Harvest infographic brings you Herbes de Provence!

An infographic on cultivating the herbs of Herbs de Provence.

Are You Really Going to Eat Those Mushrooms?

Mon, 06/30/2014 - 9:06am

I don’t have to look outside to know that it has been raining lately. My phone has been ringing off the hook with calls from the Illinois Poison Center requesting help with potential mushroom poisoning cases. I helped with four different cases today! Three of them involved children; the other was a case of an adult eating something that “looked good to eat.”

Chlorophyllum molybdites, the green-spored lepiota, was the mushroom du jour. Three of the cases involved this toxic mushroom that is commonly found in yards after summer rains. It looks lovely, and it usually won’t kill you, but I’m told that it makes one sick enough that people think that they might die. Symptoms involve vomiting and/or diarrhea, often severe, starting one to three hours after ingestion. This is the most commonly eaten toxic mushroom in the United States.

 Suburban lawn covered with mushrooms.

It might seem like a bumper crop of free eats in your lawn, but Chlorophyllum molybdites is toxic.

Today’s other culprit was Panaeolina foenisecii, known as the lawn mower’s mushroom, also commonly found growing in lawns. Unlike Chlorophyllum molybdites, this is no beauty. It is an LBM (little brown mushroom). It too can cause gastric upset and has been reported to cause slight hallucinations in some cases, but never in the numerous cases in which I’ve been involved.

 Panaeolus foenisecii, or lawn mower's mushroom

Panaeolus foenisecii, or lawn mower’s mushroom, is also nonedible. (Photo with permission Michael Kuo, mushroomexpert.com.)

Not all mushrooms growing in lawns are toxic. But the only way to tell is to know what the mushroom is (identify it). There are no short cuts or tricks to knowing whether a mushroom is toxic or not, so think before you eat! There are a number of mushroom books that can help (I’m partial to Wild Edible Mushrooms of Illinois and Surrounding States by my colleague Joe McFarland and me). And a great way to learn mushroom identification is to join a club like the Illinois Mycological Association.

Identifying mushrooms and plants for the Illinois Poison Center and hospitals is something that I and other Chicago Botanic Garden staff gladly do. Freely sharing our expertise is part of the Garden’s commitment to the region.

©2014 Chicago Botanic Garden and my.chicagobotanic.org

Gardening As We Age

Sun, 06/29/2014 - 8:53am

If you’re reading this article, you’re likely familiar with some of the challenges facing older folks: your muscles may get weaker and ache more readily. Falls can do more damage. Your energy and endurance may wane, and your skin may get thinner. Your eyesight and memory many not be as sharp, and your fine motor skills may become less coordinated.

What can the estimated 85 million U.S. gardeners do to continue gardening as they age? Gardening provides so many physical and emotional benefits that it’s well worth pursuing. The activity may even improve problems associated with aging, such as depression, osteoporosis, diabetes, and poor sleep.

 Garden volunteer Lauren waters lettuce seedlings in the greenhouses.

Keeping active in the garden is what our volunteers love best.

So let’s explore some ideas that might help you continue gardening despite these challenges. I’ve found that prevention, preparation, positioning, and partners—the four “P’s,” if you will—enable many older gardeners to carry on.

There is no better place to start than prevention. Since recovery takes longer as we age, let’s make sure we have less to recover from. Make a solemn oath not to go out to the garden until you are wearing proper footwear! Even if you plan to just survey the yard while barefoot with your first cup of coffee, danger lurks! Without shoes, you are more likely to fall or sprain an ankle. The damp grass can be slippery, and uneven surfaces can lead to a twisted ankle. Falls can lead to serious complications and are best avoided. 

Take a few minutes to limber up your joints, especially your back and legs, before you start working in the garden. You will be much more comfortable if your muscles are warmed up. Surprising them by pulling a stubborn weed can cause pain and injury that could have been avoided. 

Remember to protect your skin. That means sunscreen, a hat, gloves, and loose, light clothing. Invest in a pair of really good gloves that you will keep on no matter what the task. Cuts and abrasions in the skin of the hands are an invitation to infection. Likewise, protect your eyes from extreme brightness with sunglasses. 

Prevention even applies to the end of a day in a garden. Make sure to put away all tools and to coil all hoses away from walkways. Painting the handles of tools with bright colors make them easier to spot in the garden or lawn. 

Preparation is the next area where the time spent will be repaid handsomely.

 A container box planting of rosemary, sage, eggplant, and smaller blooms.

Containers along a path are an elegant solution to reducing overall garden space, and making seasonal plantings easier to maintain.

Begin with a critical appraisal of the areas you tend. Note what you enjoy most as well as what you dread doing. Look at quantities of plant material, and consider the age and condition of your trees and shrubs. This is an opportunity to make some well-considered decisions and create your ideal garden. Whether you implement changes all at once or gradually, your ideal should include your favorite plants and tasks in manageable proportions. 

If you do a lot of pruning regularly, decide if that is pleasurable to you. If not, hunt for some woody plants that maintain their shape naturally. If your perennials have grown into huge beds, decide if you would be just as happy with less. If so, remove your extra perennials and offer to friends or garden clubs. 

If you have been forceful and unsentimental with your removal decisions, you are likely left with some empty areas that need to be filled. This is a critical juncture. In order to avoid swapping one huge garden for another, see if you can cluster your remaining plants into smaller beds. Absorb some of the newfound space with trees or shrubs that provide structural interest, but are low in their demands. Of course, you can always plant more grass, but groundcovers do a nice job with less chemicals and mowing. Another possibility is to begin raising your garden to an easy-to-reach height. Use containers or create raised beds so that you can tend the plants without getting down to ground level. Perhaps all that space where plants have been removed can be re-envisioned as walking paths among containers and beds. 

Positioning is the third area to think about.

As you revise your garden, keep in mind that reaching down to ground level and up over your head are positions that demand a lot of energy. You will tire quickly unless you can work more in the midrange of your reach. Containers and raised beds bring the soil level up nicely. A raised bed that allows a comfortable approach with a knee space for sitting while facing the bed is ideal. A ledge for side sitting works for short periods of gardening. Try using a pulley system to bring hanging containers down to a workable level and then raise them back up again. 

Finally, let’s think about partners.

 Two scoop-shaped grip-handled trowels with serrated edges combine two gardening tools into one.

These scoop-shaped, grip-handled trowels with serrated edges combine two gardening tools into one.

Partners in gardening can be human—perhaps hired help for the most demanding or onerous tasks, such as removing weak trees. Partners can also be the wonderful tools that bolster your body’s ability. A tool that has good leverage, sharpened edges, and smooth operation of moving parts is a joy to work with. An increasing number of ergonomic tools are on the market. Look for larger, nonslip grip surfaces, handles that allow for two-handed manipulation, tool holders that distribute the workload over more than one joint, and carriers that keep tools safe and handy. 

Prevention, preparation, positioning, and partners can have you gardening for a lifetime. Such a healthy hobby is worth the time and effort it takes to keep it enjoyable.  

©2014 Chicago Botanic Garden and my.chicagobotanic.org

Candling in the Japanese Garden

Wed, 06/25/2014 - 9:03am

Have you been to the Elizabeth Hubert Malott Japanese Garden lately? If you have, you probably saw some of the garden staff perching in the branches of the niwaki. We’re not building nests or hiding out; we’re candling.

 Niwaki near the Japanese Garden bridge.

In early spring, a niwaki near the bridge stands in need of candling.

Niwaki

Niwaki, literally translated, means “garden tree.” Some people think of niwaki as big bonsai, but that relationship isn’t exactly right. Bonsai translates to “tray (or pot) planting.” While we may think of niwaki as big bonsai, we should try to think of bonsai as niwaki in a pot. The purpose of the two arts are the same; they represent the essence of the tree.

If you consider how bonsai and niwaki are styled, they give the impression of age. The trees may be windswept or upright, often with gnarled bark and wide trunks. We achieve these effects by holding branches vertically with string tied to the ground, with fall pruning, and with candling in both spring and summer.

What’s candling?

In spring, we all know things start to grow again: seeds sprout, perennials push out growth from the roots, and trees break dormancy. In pine trees, these shoots of new growth are called “candles.” When we candle, we break off part of the new growth to stimulate growth from lower nodes. (In other plants, we often refer to this as “pinching.”)

 Closeup of the tip of a pine branch, showing new growth.

A closeup of this Pinus sylvestris shows where the candle was broken last year and where you expect the new growth to emerge.

The result of breaking these candles is that the new growth spreads more horizontally than vertically, and the density of the pads increase, which makes them appear more lush and healthy over time. We never purposely take off an entire candle, because it removes the most actively growing point and takes longer to recover.

Why candle?

The pine shoots that emerge in spring are called candles for a reason: they tend to be very tall, skinny cylinders like taper or dinner candles. If we let this growth continue, the growth from one pad would grow into the next pad within a few short years. By the time this would happen, much, if not all the original pad would be woody, old, and almost impossible to repair. So in order to maintain the appearance of these trees, we need to candle every year. 

 Uncandled new growth on the Japanese Garden pine trees.

If allowed to grow, these new shoots would quickly take over.

How long does it take?

There are 180 trees in the Malott Japanese Garden trained in this style. Each tree can take anywhere from eight hours to multiple days, depending on the size and on the person who is working on it. Most of the trees at the entrance to the garden will take eight hours for some of our speedier employees. Most days, during our regular hours, you can expect to see between two to five employees in the trees.

©2014 Chicago Botanic Garden and my.chicagobotanic.org

The Ultimate Play Date: Kids + Nature

Mon, 06/23/2014 - 1:37pm

School’s out. The first official day of summer has come and gone. Time for life to move outdoors.

For some kids (OK, some caregivers, too), heading out to the backyard, the beach, the parks, and the forest preserves can feel daunting—what do you DO once you’re out there?

“Hands in earth, sand, mud: building, digging, sewing, baking—these are what humans DO.”

 A strip of astroturf is covered with an excercise course for ants made from twigs, stones, and other natural objects.

Build an ant playground out of sticks! Sue Dombro of the Forest Preserves of Cook County gave us tips for building one, adding this telling comment: “My daughter used to do this all the time, and now she’s a wildlife biologist.”

For fun, interesting, and education-based answers, we turned to a fun, interesting, and education-based crowd: the 190 teachers, home educators, day care providers, park district staff, museum employees, librarians, and just-plain-curious caregivers who came together at the Garden recently for our first Nature Play conference in May (sponsored by the Chicago Botanic Garden, Chicago Wilderness, and the Alliance for Early Childhood).

That morning, opening remarks were short, but sweet. A few thought-provoking highlights are quoted here. Then we did what any group of early childhood-oriented people would do: We all went outside to play.

At our outdoor “playground,” 19 organizations shared their fun, interesting, and education-based ideas for playing outside. You may recognize many from your own childhood.

1. Pick Up a Stick

How cool is this? In 2008, the stick was inducted into the National Toy Hall of Fame! It’s in great company: the jump rope, dominoes, the Frisbee, Tinkertoys and, yes, the Easy-Bake Oven are co-recipients of the honor. The possibilities of the stick are endless—it’s a musical instrument, a light saber, a wand, a fishing pole, a giant pencil for drawing in the dirt, a conductor’s baton, the first leg of a tepee, and anything else a child says it is.

2. Learn to Lash

If one stick is interesting, a pile of sticks has real 3-D potential. The art of lashing teaches kids to turn something small—two twigs lashed together—into something big: a ladder, a lean-to, a stool, a swing.

3. Find the Art in Nature

Twigs + stones + leaves + “tree cookies” + seeds = a nature “painting,” a sculpture, an imaginary animal, backyard trail markers, or utterly simple, charming drawings like the happy face made out of seeds shown with our headline.

“For children, the most powerful form of learning is with their hands.”

 A squirrel made from tree cookies, pine cones, acorns.

Imagination can run wild when kids are outside.

4. Nature as Paintbrush

Sure, you can use a standard brush to paint with, but feathers, pine needles, and arborvitae segments not only expand the creative possibilities but also feel wonderfully different in the hand.

5. Kid-Made Kites

Send the imagination soaring with a simple paper bag and a couple of kitchen skewers—in moments, it’s a kite! And then there’s the process of decorating it with ribbons and streamers…

6. Cricket Bug Box

Catch a cricket (or buy a dozen for $1 at the pet shop). Friendly and chirpy, crickets are many kids’ first experience with the insect world. Even little kids can collect the foliage, food scraps, and water-soaked cotton balls to accessorize a temporary shoe-box habitat.

“Nature is children’s real home.”

 A log and magnifying glass.

What’s under that log? Life.

7. Lift a Log

One of the simplest of all outdoor projects: lift up a log that’s been sitting on the ground and be amazed by the tiny wildlife that lives­ underneath it! Don’t forget to bring your magnifying glass.

8. Make a Magic Circle

Tuck a few wooden embroidery rings into a backpack. Placed on the ground in the woods, or the garden, or the sand, they become magical circles for kids to explore. What’s in yours?

9. D.I.Y. Dyeing

Rainy days need projects, too. Natural dyes made from vegetables (beets, onions), fruits (grape juice), or spices (turmeric, chili powder) transform undyed yarn or fabric into a personal style experience.

10. Paint Chip Color Hunt

One quick visit to the paint store can send kids off to hunt for hours, as they try to match nature’s colors to the humble paint chip card. (Handy to keep in the car for unexpected delays, too).

 A variety of paint chip cards with flowers that match the colors on the chips.

Simple but engrossing: match the colors in nature to the colors on a paint card.

Looking for fun things to do with the kids this summer? June is Leave No Child Inside month, so Chicago Wilderness/Leave No Child Inside has organized all sorts of ideas for you on Pinterest!

©2014 Chicago Botanic Garden and my.chicagobotanic.org

The Traveling Thatcher

Sun, 06/22/2014 - 8:55am

The arbor house in the Elizabeth Hubert Malott Japanese Garden was re-thatched recently by William Cahill, a professional thatcher, who gave us a short interview on the process, and how he learned to thatch.

A few things that thatcher William Cahill doesn’t tell you in this video:

  • He is one of only two thatchers in the entire United States.
  • He has his own forge and makes some of his own tools.
  • In the video, he wields a leggett and a Dutch mallet.
  • The water reed used for the roof is so sharp that it can cut your hand.
  • He has thatched with heather, bamboo, willow, water reed, and eucalyptus.
  • While Ireland and Japan are best known for thatched roofs, Africa thatches the most, with more than two million thatched structures.
  • His roofing résumé is fascinating: structures at Winterthur, Grey Gardens, and Lotusland; plus flower shops, sheep houses, potting sheds, museums, wigwams, churches, faerie houses, zoo pavilions…and William Butler Yeats’ home in Galway, Ireland. Check out Cahill’s amazing work at roofthatch.com.

We could listen to his beautiful Irish accent all day.

Video not working? Watch the video at http://youtu.be/gqyFXZJpdWI.

©2014 Chicago Botanic Garden and my.chicagobotanic.org

For the Ages: the English Walled Garden

Sat, 06/14/2014 - 8:33am

Step past the sleepy stone lion, breathe in the cowslip primrose, and listen to the water trickle into an eighteenth-century lead cistern—the feeling is as timeless as the tiny thyme plants growing between the hand-pressed bricks. So how do we preserve that timeless feeling while making sure the English Walled Garden withstands the rigors of time?

 An aerial view of the garden displays its perfect ordered chaos.

Work is underway to enhance the English Walled Garden’s magestical tapestry.

Dedicated in 1991 by Princess Margaret, the younger sister of Britain’s Queen Elizabeth II, the English Walled Garden features six garden rooms, surrounded by boundaries made of stone, brick, hedges, and trees. (At the dedication, Princess Margaret, by the way, wore a heavy, royal blue coat, buttoned to the collar; in a one-minute speech, she thanked the Garden for ensuring the authenticity of the English Walled Garden, according to a Chicago Tribune story. But we digress.)

 Planted in a checkerboard design are alternating boxwood and artemesia.

The geometric Checkerboard Garden features a formal study of contrast in texture and color.

Like all gardens, this one is subject to constant change. Some plants overgrow their space and need pruning. Trees cast shadows over sun-loving perennials. And some plants succumb to disease or insects. Through generous funding from the Woman’s Board of the Chicago Horticultural Society, the English Walled Garden is updated periodically. Renovations are made in consultation with the garden’s designer, renowned landscape architect John Brookes, Member of the British Empire (MBE).

Brookes most recently toured the garden in 2012 with Chicago Botanic Garden staff members, including Tim Johnson, director of horticulture, and Heather Sherwood, senior horticulturist. This year, as part of a new restoration project, the staff is rethinking the plantings. Some plants will be replaced with varieties that have more desirable qualities, such as disease resistance, increased vigor, a longer bloom period, or lower maintenance. “We’re going back to the original design plan and where it called for blue iris, we’ll work to find varieties that are new to the Garden’s collection and that fit the parameters of the original design,” Sherwood said.

“We’re also simplifying the diversity of the plantings at John’s suggestion,” Johnson added. “It’s a complicated, multilayered process that will be done in phases.” One high-priority project will be to overhaul the perennial borders so visitors can continue to experience the garden throughout the year.

 A view through the English Walled Garden, with roses draping over a myriad of flowers in bloom.

True to Brookes’ vision, full plantings overflow their borders in the garden.

In designing the garden, Brookes said his intent was to present a typical period English country garden that would evoke as many of the senses as possible. The garden “should be visual, of course, with color, but also scent and texture in the planting, and a feeling of it all not being too immaculate,” Brookes said. “Plantings should be full and almost overflowing their borders. It should be a joyous and restful place above all else.”

The Woman’s Board of the Chicago Horticultural Society is in its fourth year of “Growing the Future,” a $1 million pledge to the Chicago Botanic Garden. Proceeds from this event support fellowships for the plant biology and conservation graduate program, a collaboration between the Garden and Northwestern University.

This post was adapted from an article by Nina Koziol that appeared in the summer 2014 edition of Keep Growing, the member magazine of the Chicago Botanic Garden.

©2014 Chicago Botanic Garden and my.chicagobotanic.org

Eating Weeds

Tue, 06/10/2014 - 9:16am

If you ever find yourself grumbling over the dandelions that make their home in your lawn, or staring angrily at the purslane popping up in your vegetable garden, I have a suggestion for you: make a salad.

You may be familiar with the concept of foraging for weeds. I first became interested in the subject in college, when I realized that free food was everywhere once you knew where to look. (The reality soon set in that most of this “free” food was actually growing on lawns and private property.) Whenever you forage weeds and wild plants you have to be careful that what you take isn’t getting sprayed with herbicides—which is why I recommend only harvesting weeds from your own yard, or places you know have uncontaminated soil (and aren’t sprayed). It’s also very important to know exactly what you’re eating. Sometimes weeds have look-alikes that can be upsetting to the stomach or downright deadly. Others, of course, you can easily recognize from a distance, like yellow wood sorrel.

 Yellow wood sorrel in bloom.

Great as a snack or a garnish, Oxalis is a tasty edible weed.

Oxalis stricta

Oxalis stricta, also known as yellow wood sorrel or lemon clover, is an annual weed that you can find anywhere…and everywhere. It spreads aggressively from its seedpods—which can explode on contact!

It only takes a brief sampling of the leaf to figure out why this weed is also called sour grass. The plants are full of oxalic acid, which is dangerous to humans in large amounts, but relatively harmless in small doses. The oxalic acid in the plant gives it a wonderful sour taste that makes for an excellent addition to salads. Oxalis grows commonly in lightly to heavily shaded garden areas. Look for them under plants like hostas.

 Dandelion blooming in the lawn.

The long, lion-toothed leaves help identify suburban lawn villain Taraxacum officinale, but if you ever have a doubt, look for the aster-esqe yellow blooms.

Taraxacum officinale

Taraxacum officinale, or dandelions, are bothersome weeds, but they are truly “gourmet.” Dandelions get their name from their toothed leaves which are reminiscent of lion’s teeth, or as the French would say, “dent de lion.”

In its long botanical history, the dandelion has been used medicinally, but also as food. Dandelion roots, leaves, and flowers are entirely edible. Roasted, the roots can make for a caffeine-free coffee substitute. The young leaves make for bitter but interesting additions to salads. The plants can also be deprived of sunlight until the leaves become pale, which will change the flavor of the leaves to make them more palatable. The flower buds can be fried and eaten, while the open blooms can be used to make dandelion wine!

 Purslane poking up through garden mulch.

Keep an eye out for the  fairly drought resistant  Portulaca oleraceae in areas where the ground tends to crack.

 

Portulaca oleraceae

Purslane (Portulaca oleraceae) is a weed that you can find in sunny garden areas. They have succulent, red to green, low-spreading stems with flat, paddle-shaped leaves and bright yellow flowers. Purslane actually has an ornamental relative called moss rose (Portulaca grandiflora), which have leaves that are more pointed than flat, and much larger flowers. Though they are also edible, why bother when you have purslane growing naturally? Look for purslane in sunny areas, particularly where the ground can get dry. Harvest purslane any time before the flowers appear, because they can become quite bitter after flowering. Purslane is also incredibly nutritious, rich in Omega-3 fatty acids, and high in Vitamins A, C, and E, as well as magnesium, potassium, and iron, just to name a few. Try it raw, or in a stir-fry!

 Lamb's quarters in the garden bed.

Chenopodium is an easy weed to scarf up while working in the garden.

Chenopodium album

Another common edible weed is Chenopodium album, also called lambs’ quarters, or goosefoot. It will grow in sunny to partly shady areas and is high in Vitamins A and C. Like Oxalis, it also has high amounts of oxalic acid, so remember to enjoy it in moderation. I prefer to eat the young seedlings which only have 2-3 sets of leaves. This makes for an easy snack while you’re in the garden. 

Steer clear of Chenopodium’s southern cousin, epazote (Chenopodium ambrosioides or Dysphania ambrosioides). Native to Central America, South America, and southern Mexico, this weed can now be found on roadsides in North America as well. While epazote—whose long skinny leaves do not resemble a goosefoot—is used medicinally for a number of purposes, high doses can can cause severe dermatitis or allergic reactions. 

 Spiderwort in bloom.

Tradescantia is more of a beautiful garden edible than a weed.

Tradescantia

As our final edible weed, I debated including Tradescantia, or spiderwort, in this list. Though it can spread in the garden, it is not anywhere as aggressive as the other weeds in this list. It is also commonly grown for ornamental purposes. In fact, I’m planning to order some of Chicagoland Grows’ Tradescantia ‘Tough Love’ —a reddish-purple-flowered cultivar—for my garden next year when it is released!

The wild plants vary a great deal in size from 1 foot to 4-5 feet tall, depending on species. The small, three-petaled flowers are often blue, but also come in purple, pink, and white. The name spiderwort may come from the fuzzy, webbing-like stamens of the flower, or from the way the mucilaginous substance in the stems will form thin, web-like strands when broken. If you’re planning on eating this one, peel the leaves off the stem and cook them like asparagus. You can also chop up the stems (or leaves) and fry them. But don’t stop there—the flowers are also tasty when raw. Since they usually last for just one day, you don’t have to feel guilty about eating them either! Plus, since they’re native plants used to grazing animals, they can take the abuse!

Interested in learning about more weedy cuisine in your yard? Join environmentalist, author, and forager Melany Vorass Herrera for The Front Yard Forager Workshop on Friday, June 20, from 6 to 8 p.m.

©2014 Chicago Botanic Garden and my.chicagobotanic.org

Plant Breeding Program Takes Perennials to New Heights

Sun, 06/08/2014 - 1:10pm

Interested in new perennials for your garden? How about ones that have proven to be exceptional—fragrant, colorful, drought tolerant, resistant to disease and pests, and hardy in the Midwest and similar climates? Just turn to our scientists, who have done the legwork for you through the Chicago Botanic Garden’s plant breeding and evaluation programs.

Breeding and selecting new perennials is a long, intense process that begins with cross-pollinating two plants, or moving pollen by hand from the flowers of one plant to the flowers of another plant with different traits. The two related plants—which ideally will produce exceptional offspring—are selected for breeding based on desirable attributes.

 Jim Ault poses in a bed of bright pink- and purple-blooming asters he developed at the Garden.

Jim Ault, Ph.D., with Symphyotricum (aster) hybrids developed at the Garden

 A closeup of the rich purple buds of Twilite false indigo.

Twilite false indigo (Baptisia × variicolor ‘Twilite’)

 Using tweezers, Jim Ault hand-pollinates a Baptisia.

Pollinating Baptisia

“In the best-case scenario, from the first cross to the final plant worthy of introduction, it takes about seven years, maybe eight to ten. I have to think long-term in generation time, from seed to first bloom to maturity,” said Jim Ault, Ph.D., plant introduction manager and Gaylord and Dorothy Donnelley Director of Ornamental Plant Research.

The most promising new plants are propagated by cuttings or tissue culture and then scrutinized by the Garden’s Plant Evaluation Program, managed by Richard Hawke. He compares the plants to cultivars and species already in the trade to ensure that the plants from the breeding program are unique and worthy of introduction. Hawke also recommends plants for use as parents in the breeding program.

 Richard Hawke crouches down, examining the progress of a cultivar planted at the Garden.

Richard Hawke at work

“The public can see about 80 percent of the breeding program plants as we are growing them in the ground in the evaluation gardens,” Dr. Ault said. Plants with the highest marks move to licensed commercial nurseries that also conduct field and container trials and then propagate the new plants for sale to home gardeners and the horticultural trade.

In recent years, popular offerings from the breeding program have included the first orange coneflower ever released, Art’s Pride coneflower (Echinacea ‘Art’s Pride’), and Forever Pink phlox (Phlox ‘Forever Pink’). “The interest in ‘Forever Pink’ has exploded,” Ault said. “It has three weeks of peak bloom in late May to early June and then it repeat-blooms on about 10 percent of the plant all summer and fall. It’s compact and, unlike other summer-blooming phlox, has had no powdery mildew whatsoever.”

You can expect to see more noteworthy perennials in coming years. Ault is hybridizing several types, including ground-cover phlox, asters, and other genera. “Something really wonderful should bloom this spring out of the hundreds of new seedlings that we’re growing,” said Ault.

Visit chicagobotanic.org/research/environmental/breeding for a full list of the perennials released commercially through the Garden’s Plant Breeding Program.

 A closeup of the unusual bright orange color of Art's Pride coneflower.

Art’s Pride coneflower (Echinacea ‘Art’s Pride’)

 A bed of a dozen plantings of Forever Pink phlox in full bloom.

Forever Pink phlox (Phlox ‘Forever Pink’)

 Tidal Pool prostrate speedwell.

Tidal Pool prostrate speedwell (Veronica ‘Tidal Pool’)

Support for the plant evaluation program is provided by the Bernice E. Lavin Evaluation Garden Endowment, the Woman’s Board Endowment for Plant Evaluation Research and Publication, and the Sally Meads Hand Foundation.

This post was adapted from an article by Nina Koziol that appeared in the spring 2014 edition of Keep Growing, the member magazine of the Chicago Botanic Garden.

©2014 Chicago Botanic Garden and my.chicagobotanic.org

Today’s Harvest: Lettuce

Thu, 06/05/2014 - 9:58am

Learn to love the leaf!

Home-grown garden lettuce beats grocery store lettuce for taste, nutrition, and freshness. Planting seeds 2 weeks apart in spring ensures you can enjoy fresh greens all summer long. More tips follow in our Today’s Harvest veggiegraphic: lettuce!

Infographic on cultivating and harvesting lettuce.

Parents: Read This

Wed, 06/04/2014 - 9:51am

It’s a fact: kids can lose valuable reading skills during summer break. It’s called “summer slide,” and the loss can be large—two months worth of lost reading skills is not unusual over the summer, and teachers will tell you that retraining in fall regularly takes up precious class time.

It’s also a fact: by reading just 20 minutes per day, your child maintains his or her reading level through the summer. 

At the Lenhardt Library, our creative librarians have come up with a fun way to help you make the latter happen.

 There's a Hair in my Dirt! A Worm's Story.

 An Absolute Beginner's Guide.

 Compost Stew, An A to Z Recipe for the Earth.

 Attracting Butterflies to your Garden.

 The Plant Hunters.

 Jardineria Facil para Ninos.

Sign up now to be a Summer Nature Explorer at the Chicago Botanic Garden. Between May 31 and August 17, your child can read books and have fun at drop-in activities, earning stamps and prizes—encouragements that help kids stave off reading loss.

It’s also our library’s link to the National Science Foundation’s STEM program (Science, Technology, Engineering, and Math) that aims to increase science skills in the United States. Here’s the foundation’s interesting and fact-filled site: www.nsf.gov/nsb/sei/edTool.

Here’s how our Summer Reading and Nature Program works:

  • Sign up at the Lenhardt Library. Take home a reading and activity log.
  • Read a book; get a stamp. The log helps you keep track of your books.
  • Play at a Family Drop-In Activity; get a stamp. Great for reluctant readers who learn critical thinking skills in different ways.
  • Earn 5 stamps; get a prize. Bring your child to the library for the prize—we don’t want to give away the surprise!
  • Earn 10 stamps; get a prize. At 10 books, the reader earns the temporary frog tattoo shown below.
  • Earn 15 stamps; get a prize. Hint: it’s something to tuck into your backpack for school.
  • Earn 20 stamps; get a big prize. We’ll hand the proud reader a free ticket for his/her admission to Butterflies & Blooms. (Parents, you can sign up, read some great books, and earn your own free ticket, too!) 
  • Here’s the link for more details: chicagobotanic.org/library/summer_reading.

 A cartoon of a frog reading a book.

Not reading yet? Even the pre-K set can sign up! Parents/adults can earn stamps/prizes for littler kids by reading books to them—that’s how a lifelong love of reading begins! (Of course, little kids love getting the same treats as their already-reading siblings, too.)

Of course, members have check-out privileges at the library, but nonmembers are welcome to sit and read—the reading nook (pillows on the floor, kid-sized reading table) has been known to attract many a bookworm parent, too. On the library shelves, look on book spines for:

  • Yellow dots = Books for the 2 to 6 crowd
  • Yellow dots with blue stars = For readers 7 to 10
  • Yellow dots with red stars = Spanish-language books for kids
  • Blue tape = New to our collection!

Family Drop-in Activities shake up the routine with a roster of unusual, nature-based activities: kids might dissect a seed at the Grunsfeld Children’s Growing Garden…or search for underwater creatures at Kleinman Family Cove…or make a samurai mask at the Elizabeth Hubert Malott Japanese Garden. Drop-in activities take place every summer day—for the line-up and locations, go to chicagobotanic.org/forfamilies.

And did we mention that it’s all free?

Happy summer reading, and we look forward to seeing you at the circulation desk!

©2014 Chicago Botanic Garden and my.chicagobotanic.org

Year-End Gifts for Teachers

Mon, 06/02/2014 - 8:55am

Having three daughters in middle school means trying to find a nice way to show my appreciation to all of their teachers. When I say “all” for the middle grades, that is not just three teachers any more, because they have separate teachers for each subject, as well as “special” teachers for art, gym, music, and library. And then there is the office staff members who were really nice and helpful during the year.

Do I need to give everyone something? Certainly not. But I would like to end the year on a pleasant note and say “Thanks!” for serving my three children—without spending too much money, that is. The answer is plants (which is what you expected from a Chicago Botanic Garden blogger, right?). 

 A flat of 3-inch lavender pots.

This flat of lavender came in pots with care labels. All we need to do is add thank-you notes.

Every year, I go to a local nursery and buy a few flats of herbs or flowers. I prefer going to a local, small nursery or greenhouse rather than a large franchise store that sell other products. The plants tend to be in better condition, and supporting local businesses is good for the community. And it’s fun meeting and getting to know small business owners.

My daughters help choose the plants, which means we usually get purple flowers of some kind. If the plants come in cell packs, we transplant them to inexpensive containers. Otherwise, we give them as they come from the nursery. It does not have to be fancy to make everyone happy.

We make a thank-you note on the computer. It includes information about how to care for that plant. Then we use use bamboo skewers (left over from making rock candy!) or plastic forks to hold them in place.

 An oregano plant with a thank-you note attached.

We used a bamboo skewer to attach a thank-you note and oregano care instructions.

 Lily of the valley plant, with thank you not held in the pot through the tines of a fork.

One teacher requested a plant for a shady yard, so we included some lily of the valley in the selection, and used a fork to attach a thank-you note.

I set aside one plant for each daughter to personally present to her homeroom teacher. I bring the rest of the plants to the school office during the last week. After years of doing this, the office staff now anticipates the delivery as if it’s Christmas. (I also bring a package of paper lunch bags so teachers have a clean way to carry their plants home.)

The principal makes an announcement during the school day that any teacher who would like a plant can pick one up in the office—first come, first served. Even if a teacher doesn’t want to take a plant (I’m pretty sure the computer lab instructor at our school is not interested), he or she can enjoy looking at them and smelling them in the office. That takes care of everyone I want to thank. All plants are claimed by the end of the day.

 Seed packed with a label saying, "Thanks for planting the seeds of knowledge."

Creative wording makes writing the notes fun.

If this works for me, it can work for you, too. If plants are too much of a hassle or expense, consider giving seeds instead. Attach a ribbon with a note to let the teacher know your gratitude. You can say something cute such as “Thanks for helping me grow!”

Or use a clever rhyme:

Just like the year I spent in your room, I hope these seeds germinate, grow up, and bloom.

Looking for another idea? There’s always Bottle Cap Bouquets, which delight teachers and mothers alike. Cheap and cheerful!

I wasn’t sure how much the teachers appreciated the plants until one teacher asked my daughter if I would be bringing plants again, and what kind they might be. She was looking forward to the end of school, but she was also looking forward to taking home a plant to start the summer.

©2014 Chicago Botanic Garden and my.chicagobotanic.org

Pollinator 411

Fri, 05/30/2014 - 9:10am
 Pollinator infographic.

Plant Conservation Is Happening Right Over Your Head

Thu, 05/29/2014 - 11:31am

What if the next plant conservation project wasn’t down the street, or in the neighboring county, or far away in the wilderness? What if it was right above your head, on your roof? In our increasingly urban world, making use of rooftop space might help conserve some of our precious biodiversity in and around cities.

 Ksiazek bending to examine blooming sedums on Chicago's City Hall green roof.

The green roof on Chicago’s City Hall supports an amazing diversity of hundreds of plant species.

Unfortunately, native prairie plants have lost most of their natural habitat. In fact, less than one-tenth of one percent of prairies remains in Illinois—pretty sad for a state whose motto is the “Prairie State.” As a Chicago native, I found this very alarming. I thought, “Is it possible to use spaces other than our local nature preserves to help prevent the extinction of some of these beautiful prairie plants?” With new legislation at the turn of the century that encouraged the construction of many green roofs in Chicago, it seemed like the perfect place to test a growing hypothesis I had: maybe some of the native prairie plants that were losing habitat elsewhere could thrive on green roofs.

This idea brought me to the graduate program in Plant Biology and Conservation, a joint degree program through Northwestern University and the Chicago Botanic Garden. Here, I am investigating the possibility that the engineered habitats of green roofs can be used to conserve native prairie plants and the pollinators that they support.

 Ksiazek examines plants in a prairie, taking data.

Which plant are you? In 2012, I surveyed natural prairies to determine which species live together.

Since I began the program as a master’s degree student in 2009, I’ve learned a lot about how native plants and pollinators can be supported on green roofs. For my master’s thesis, I wanted to see if native wildflowers were visited by pollinators and if they were receiving enough high-quality pollen to makes seeds and reproduce. Good news! The nine native wildflower species I tested produced just as many seeds on roofs as they normally do on the ground, and these seeds are able to germinate, or grow into new plants.

Once I knew that pollinator-dependent plants should be able to reproduce on green roofs, I set out to learn how to intentionally design green roofs to mimic prairies for my doctoral research. I started by visiting about 20 short-grass prairies in the Chicago region to see which species lived together in habitats that are similar to green roofs. These short-grass prairies all had very shallow soil that drained quickly and next to no shade; the same conditions you’d find on a green roof. 

 Ksiazek poses for a photo among prairie grasses.

Plant species from this dry sand prairie just south of Chicago might also be able to survive on green roofs in the city.

 Plant seedling.

A tiny bee balm (Monarda fistulosa) seedling grows on the green roof at the Plant Science Center at the Chicago Botanic Garden.

 Hand holding a seedling; paperwork is in the background, along with a seedling tray.

One of my experiments involves planting tiny native seedlings into special experimental green roof trays. They’re now on top of the Plant Science Center. Go take a look!

I’m now setting up experiments that test the ability of the short-grass prairie species to live together on green roofs. Some of these experiments involved using seeds as a cheap and fast way of getting native plants on the roof. Other experiments involved using small plant seedlings that may have a better chance of survival, although, as any gardener could tell you, are more expensive and labor intensive than planting seeds. I will continue to collect data on the survival and health of all these native plants at several locations, including the green roof on the Daniel F. and Ada L. Rice Plant Conservation Science Center at the Garden.

Ideally, I would continue to collect data on these experimental prairies to see how they develop over the next 50 years and learn how the plants were able to support native insects, such as pollinating bees and butterflies. But I didn’t want my Ph.D. to last 50 years so instead, I decided to collect the same type of data on green roofs that have already been around for a few decades. Because the technology is still relatively new in America, I had to go to Germany to collect this data, where the history of green roofs is much older. Last year, through a Fulbright and Germanistic Society of America Fellowship, I collected insects and data about the plant communities on several green roofs in and around Berlin and learned that green roofs can support very diverse plant and insect communities over time. We scientists are just starting to learn more about how green roofs are different from other urban gardens and parks, but it’s looking like they might be able to contribute to urban biodiversity conservation and support.

 Ksiazek collects insects from traps on a green roof in Berlin.

I collected almost 10,000 insects on green roofs in and around Berlin, Germany in 2013.

 Closeup of a pinned bee collected from a green roof in Berlin.

I found more than 50 different species of bees on the green roofs in Germany.

Now that I’m back in Chicago and have been awarded research grants from several institutions, I’m setting up a new experiment to learn about how pollinators move pollen from one green roof to another. I’ll be using a couple different prairie plants to measure “gene flow,” which basically describes how pollen moves between maternal and paternal plants. If I find that pollinators bring pollen from one roof to anther, this means that green roofs might be connected to the large urban habitat, rather than merely being isolated “islands in the sky,” as some people have suggested. If this is true, then green roofs could also help other plants in their surroundings—more pollinating green roof bees could mean more fruit yield for your nearby garden.  

 Aerial view of Chicago at Lake Michigan, with green rectangles superimposed over building which house green roofs.

The green boxes represent green roofs near Lake Michigan. How will pollinators like bees, butterflies, and moths move pollen between plants on these different roofs? This summer, I will be carrying out an experiment to find out.

There are still many questions to be answered in this new field of plant science research. I’m very excited to be learning so much through the graduate program at the Garden and to be collaborating with innovative researchers both in Chicago and abroad. If you’re interested in keeping up with my monthly progress, please visit my research blog at the Phipps Conservatory Botany in Action Fellows’ page

 A wasp drinks water from a flower after rain.

A friendly little wasp enjoys the native green roof plants on a rainy day in Paris.

And if you haven’t already done so, I hope you’ll get a chance to visit the green roof at the Plant Science Center and see how beautiful plant conservation happening right over your head can be! 

©2014 Chicago Botanic Garden and my.chicagobotanic.org

Happy Birthday, Rachel Carson

Tue, 05/27/2014 - 4:02pm

Thank you, Rachel Carson.

peanuts2-20-1

For me, personally, Silent Spring had a profound impact. It was one of the books we read at home at my mother’s insistence and then discussed around the dinner table. . . . Rachel Carson was one of the reasons why I became so conscious of the environment and so involved with environmental issues. Her example inspired me to write Earth in the Balance. . . . Her picture hangs on my office wall among those of political leaders. . . . Carson has had as much or more effect on me than any of them, and perhaps than all of them together.

—Vice President Al Gore, “Introduction,” Silent Spring, (1994 edition), xiii

silentMy mom was a grade school teacher. During a brief period where she stayed at home with the children, she became an environmentalist. It all began with the book Silent Spring. My mother read about chemicals used in farming post-World War II and the decline of birds, and that was it; she had to take action. She remembers going to her parents’ house, and my grandfather was going around the yard, spraying DDT without protection, as his grandchildren played. He had a big bottle of DDT in the garage that had gone unnoticed until then. My mother could not believe what was happening and stopped him immediately. She had her dad throw out all pesticides. My grandfather didn’t realize there was any danger, as these chemicals promised a beautiful, American-dream green lawn. I remember at family gatherings, our family kept saying to my mother, “Elaine, what are you so worried about?”

 Mom holds her smiling baby daughter in the air.

My hero, my mother

We became a family that ate whole wheat bread, and got the 1970s equivalent of CSA (Community Supported Agriculture) boxes. I would say that this book changed my childhood.

Some highlights:

  • My mom baked organic whole wheat bread every week; it was not commercially available yet. (Imagine going to middle school with a sandwich of PB&J on badly cut homemade whole wheat bread, surrounded by kids eating bologna on Wonder Bread white. My brother and I felt so out of place at the time. (And now it would be so accepted, wonderful, and charming.)
  • We did not have a microwave.
  • No pop. No junk food. No candy.
  • Our suburban lawn had dandelions. Mom had a dandelion knife.
  • We used nonphosphate detergent.
  • We went to weird hippie health food restaurants in Chicago. For her birthday, my mom knew she would get her requested restaurant so she would pick the only organic one in town.
  • There were no TV dinners (and we could watch one hour of television a day).
  • We all got transcendental meditation mantras.

But I digress…

She was the co-founder of S.A.V.E.: Society Against Violence to the Environment. “When Zion’s nuclear power plant was being built, we felt that it was so close to a large city…I put a full-page ad in Highland Park News, and I wrote an article about nuclear waste and terrorists.”

 Dandelion knife.

A classic tool I still use today: the dandelion knife

When my mom wasn’t lying down in front of bulldozers, or arguing with the Park District of Highland Park or Highland Park High School about spraying grass that children played on, she was going door-to-door, stopping the spraying of mosquitoes in our town.

After we moved to San Diego, I remember lugging many heavy grocery bags filled with organic oranges and organic flour from San Diego State University’s co-op parking lot, ½ mile each way every week (several trips each time).

Later, when she got cancer,  she endured the remark, “Oh, you with your organic food, you got cancer?”

Now you can find organic food everywhere. Who doesn’t meditate?

Teach your children well…

New times and different challenges…now we are concerned with global warming.

As Rachel Carson said:

“We stand now where two roads diverge. But unlike the roads in Robert Frost’s familiar poem, they are not equally fair. The road we have long been traveling is deceptively easy, a smooth superhighway on which we progress with great speed, but at its end lies disaster. The other fork of the road—the one less traveled by—offers our last, our only chance to reach a destination that assures the preservation of the earth.”

 Baby robins chirping; a sign of spring's arrival.

Baby robins chirping; a sign of spring’s arrival

Thanks, Mom. You taught me about Mother Earth. I still don’t have a microwave. I eat organic food, grow some my own, and am lucky to work at a garden that cares about the environment. :)

Join us for World Environment Day, Saturday, June 7, and learn what you can do to help the environment.

©2014 Chicago Botanic Garden and my.chicagobotanic.org

Strawberries

Mon, 05/26/2014 - 3:00pm

When I was 8 years old, I traveled with my family to Przysietnica, Poland, to spend the summer with relatives. My grandparents’ farm was the home base for my adventures with cousins and siblings. We spent hours in the breezy northern hills, picking the sweetest strawberries I ever had. They grew wild and tasted like candy. We often brought some back to share with the family, but there is nothing quite like a strawberry fresh off the plant.

 Blooming strawberry plant in the garden.

First described by the ancient Romans, strawberries were first cultivated in gardens in the 1300s.

The Cultivated Strawberry

The garden strawberry is the strawberry we most often think of when we think of strawberries. This is the strawberry from the clear plastic boxes you find at the grocery store. This strawberry is Fragaria × ananassa, which has only been around for about 260 years, and has undergone a lot of breeding in that time.

Fragaria × ananassa is actually a cross of the Chilean and Virginia (or wild) strawberry, which arrived in Europe in 1712 and 1624, respectively. The hybrid plant was discovered in the 1750s and recorded in 1759 by Philip Miller, a famous English horticulturist. He referred to it as the “pine strawberry” for its taste, which was similar to pineapple.

If you’re taken aback by this assessment of flavor, you’re not alone—the modern garden strawberry has undergone a great deal of breeding, which improved firmness but did little for its taste. Some of the modern breeding programs are working to fix this problem.

Fragaria × ananassa is not the only cultivated strawberry on the market. There are more than 20 species of strawberries worldwide, with only a small portion of those being grown in gardens for eating. Some of the popular species include the musk strawberry (F. moschata), the alpine strawberry (F. vesca), the Chilean strawberry (F. chiloensis), the Virginia strawberry (F. virginiana), Fragaria nipponica, and Fragaria viridis. Most of these strawberries originate in Europe (Fragaria nipponica is Japanese in origin); the Chilean and Virginia strawberries are the only cultivated New World species. While there are many edible strawberries, these tend to be the most popular.

 Rows of strawberry plants mulched with (what else?) straw.

Strawberries planted in rows and left to their own devices will spread wildly within a few years.

Biology

Do you know how the strawberry got its name? The popular theory is that strawberries are so named because they are cultivated on straw. The truth is, strawberries were named before straw was ever cultivated. Have you ever seen strawberries growing? They spread by stolons, or above-ground roots. These stolons reach out, find a good moist spot away from the parent, and put out roots, producing a new clone of the mother plant. In this way, a single cultivar of strawberry can reproduce itself dozens of times and still be identical or nearly identical to the mother plant. The stolons that give rise to new strawberries are called “runners.” This habit of growing is what gave it its name; strawberries tend to be strewn (spread) about.

It’s generally accepted that strawberries will either produce runners or flowers. Though sometimes producing both simultaneously, the energy is usually dedicated to one task over the other. This is why there are three main types of garden strawberries: ever-bearing, day-neutral, and June-bearing. Strawberries tend to be June-bearing by nature, which means you’ll harvest your fruit in late spring to early summer. Though you sometimes end up with a second crop in fall, the June-bearing strawberry will produce runners for the rest of the year. Ever-bearing strawberries prefer to put their energy toward making fruit, so you’ll end up with few runners and strawberries several times per season. Day-neutral will produce strawberries continually throughout the year, and create the fewest runners.

The white tissue under the pistils is what swells into a red juicy strawberry

The white tissue under the pistils swells into the sweet edible “fruit”

“Fruit”

Did you know that a strawberry isn’t a fruit? It’s an “aggregate of achenes on a swollen receptacle.” Achenes are those little specks on the surface of the strawberry; these are the true fruit of the strawberry. The achenes break apart much the way that sunflower seeds do. An aggregate refers to a cluster or grouping, and the receptacle is the part of a flower that bears the sexual organs.

Seems complicated? Try this: cut a strawberry flower in half and look inside.

The female parts of the flower (pistils) are near the top center of the flower with the male parts (stamens) forming a ring around the outside. When the flowers are pollinated, the area under each pistil swells and turns red. When the whole flower is pollinated, you end up with a perfectly red strawberry.

 Time lapse of strawberry fruiting process.

Time lapse of a strawberry, flower-to-fruit, by Tomas ‘Frooxius’ Mariancik.

Humans have known about strawberries for hundreds of years, but strawberries only became commercially common within the past century, thanks to refrigerated trucks and breeding programs that gave strawberries their firmness. Ever since, they have been one of the top ten favorite “fruits” in the United States.

©2014 Chicago Botanic Garden and my.chicagobotanic.org

Grafting Tomatoes

Sun, 05/25/2014 - 8:36am

Grafted tomato plants are available at garden centers and through mail order nursery catalogs, but sell out quickly, as the idea has captured the interest of home gardeners, farmers, and professional greenhouse growers.

 Tomato graft with silicon tubing holding the graft in place to heal.

The finished tomato graft: this will be placed into a “healing chamber” for a week while the graft seals.

An ancient art and science long used on fruit trees, grafting is the placement of the tissues of one plant (called a scion) onto another plant (called a stock). The rootstock is thought to impart disease resistance and increased vigor to a less vigorous—perhaps heirloom—tomato grafted on the top, producing more tomatoes over a longer period of time.

Curious about the process and whether the price tag could be justified—grafted plants run from $9 to $18 a plant—I decided to graft some tomato plants myself and grow them out. My first foray was in winter 2013. The Chicago Botanic Garden’s propagator in the plant production department, Cathy Thomas, had just returned from a conference at Longwood Gardens, where one of the topics was grafting vegetables. She willingly supported my quest and enthusiastically discussed the details with me.

The process seemed fairly straightforward after we settled on which varieties to graft together. Deciding to graft the cultivar ‘Black Cherry’ onto ‘Better Boy’ rootstock, we worked with tiny, 3-inch-tall tomato starts, taking care that the top and bottom stems of each plant were exactly the same diameter at the place they were to be grafted. Our grafting tools included clear silicon tubing cut to 10 to 15 millimeter lengths, a new, unused razor blade, and our tomato seedlings.

Starting by sanitizing our hands, we used a new razor blade to slice the stem of the scion (top graft plant) off at a 45-degree angle. The plastic tubing, soon to be the grafting clip that would bandage the graft union, was prepared by splitting it in half. All the leaves were removed from the scion, leaving only the meristem. (The meristem is the region of stem directly above the roots of the seedling, where actively dividing cells rapidly form new tissue.) Two diagonal cuts were made, forming a nice wedge to fit into the rootstock. The rootstock was split and held open to accommodate the scion. A silicon clip was slipped around the cleft graft. Newly grafted plants were then set into a “healing chamber,” a place with indirect light and high humidity, for up to a week. In the healing chamber, the plants can heal without needing to reach for light, which can cause the tops to pop off. We placed our new grafts in a large plastic bag in the Regenstein Fruit & Vegetable Garden greenhouse. The healing began.

 Slicing the top off the rootstock tomato seedling.

Cut the root stock off at the meristem; discard the top of the seedling to avoid confusing it with the scions you will be grafting.

 Slicing the top of the meristem to insert the scion graft.

After cutting off the top of the rootstock, user the razor to vertically slice the top part of the remaining meristem.

 Removing the leaves from the tomato scion graft.

Remove the extra leaves from the scion, leaving only the top set.

 Sharpening the tip of the scion to a point.

Make two 45-degree cuts to the end of the scion to create a sharp tip to insert into the rootstock.

 The scion is inserted into the rootstock of the tomato graft.

Using the razor’s edge to pry open the split rootstock, gently insert the prepared scion.

 Closeup of the finished tomato graft.

Slice the silicone tubing open and wrap the cuff around the graft, entirely covering the graft to support the top plant and speed healing.

Two weeks later, we had a dismal one-third survival rate! Much to my relief, the lone survivor was a superlative tomato plant in almost every way. Oh, what a strong tomato we had! My excitement rose—what if heirloom tomatoes could be as delicious and more prolific and adaptable? When soils warmed, we planted our grafted tomato out in the Fruit & Vegetable Garden, positioned right next to a ‘Black Cherry’ plant growing on its own root, so the differences would be easy to discern. Our hope was that we could address some of the ins and outs of grafting for the public, and the feasibility of DIY (Do It Yourself) for gardeners. Do grafted heirloom tomatoes have more vigor, better quality, and bear more fruit than ungrafted “own-root” heirloom tomatoes? Which has a more abundant harvest over a longer period of time?

Last summer, our grafted tomato plant certainly provided the earliest harvest. Comparatively, it was earlier to fruit than the plant grown on its own root by two weeks, and was prolific throughout the season. That being said, in the organic system of the Fruit & Vegetable Garden, our soils are nutrient-rich and disease-free in large part due to crop rotation and soil-building practices. The question used in marketing “Is the key place for grafted tomatoes in a soil that has disease problems?” didn’t apply to us. Are grafted tomatoes the answer for those with less-than-ideal environmental growing conditions? For greenhouse growers unable to practice crop rotation as a hedge against a build-up of soil-borne disease, or home gardeners who contend with cool nights and a short growing season, I would say yes, I think so, but at a cost.

 Grafted tomato in healing chamber.

Place the finished graft in a humid location, out of direct sunlight, to heal for up to one week.

When planning on grafting, growers must buy double the amount of seed and need to double the number of plantings (to account for the graft failure rate) to maintain the same number of viable seedlings to plant. Cathy and I tried our grafting project again this spring and are looking forward to growing ‘Stripes of Yore’ and ‘Primary Colors’ on ‘Big Beef’ hybrid rootstock. I swapped seed for these unusual varieties with a tomato enthusiast who attended our annual Seed Swap this past February. Our rootstock has excellent resistance to common tomato diseases: AS (Alternaria Stem canker), F2 (Fusarium wilt), L (Gray Leaf Spot), N (Nematodes), TMV (Tobacco Mosaic Virus), V (Verticillium Wilt). So far, three of our eight plants are viable, healed, and strong.

We are looking forward to planting the grafted tomatoes the week of June 8 in the Fruit & Vegetable Garden, right alongside some of the other 52 varieties of heirloom and hybrid tomatoes. So whether you choose a regular or a grafted plant at the garden center this weekend, come on over! It’s time to talk tomatoes! @hilgenberg8

©2014 Chicago Botanic Garden and my.chicagobotanic.org

Lenhardt Library: New collaborations for future advancement

Fri, 05/23/2014 - 10:15am

In early May, I was gratified to hear that the Lenhardt Library’s application to become an affiliate member at the Biodiversity Heritage Library (BHL) had been accepted. BHL is an open access, all digital repository of biodiversity literature.

 View into the Lenhardt Library at the Chicago Botanic Garden.

The Lenhardt Library is open to the public. Garden members may borrow materials for 28 days.

BHL founding member libraries are based at universities, botanical gardens, and natural history museums, and include renowned institutions such as the Missouri Botanical Garden, Smithsonian Institution, Harvard University, and the Royal Botanic Gardens Kew.

These libraries contribute digital scans of books and journals in their collections. All pages are freely accessible through the BHL portal. Constantly updated, as of today, BHL includes 43,697,651 pages of biodiversity literature. Users of biodiversity literature are researchers based around the globe with nodes in Europe, Australia, and China. BHL also serves as the foundational literature component of the Encyclopedia of Life.

Plans for the Lenhardt Library’s involvement are to contribute literature unique to our collections and not held at other libraries. That may mean adding early volumes that pre-date current content in BHL, filling in missing horticulture resources, or adding volumes from the rare book collection.

Another recent Lenhardt Library affiliation is with the Center for Research Libraries (CRL). CRL is a library’s library with holdings of 5 million items. The Lenhardt Library joined this consortium of academic and research libraries to gain access to these materials to fulfill library research needs for the Chicago Botanic Garden’s staff and visitors.

Partnerships and collaborations are vital to small research libraries such as the Lenhardt Library for advancement and growth. Library collections and resource sharing ensures literature is available for study, scholarship, and scientific advancement.

©2014 Chicago Botanic Garden and my.chicagobotanic.org

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