Annual and Perennial Care

April

Forsythia AprilPlant perennials, hardy ornamental grasses, and roses. When planting bare-root roses, soak the roots in a bucket of water for several hours before planting. Be sure to choose a full-sun site before digging the hole. Remember that as soon as tall trees leaf out, full-sun areas can become partly shaded.

Divide mature summer- and fall-blooming perennials when they are 4 to 6 inches tall. Do not divide day lilies (September), Oriental poppies (July), or iris (late July) at this time.

Fertilize spring-flowering bulbs with a granular 5-10-5 or 10-10-10 mix as new green growth emerges or when they finish flowering. Remove spent flowers but allow foliage to wither completely before removing. Divide clumps of older bulbs in need of rejuvenation. Replant in sunny spot and water in well. Bulbs prefer locations that are not heavily watered during their summer dormancy. Therefore do not overplant perennial bulbs with summer annuals.If botrytis blight or bud blast was a problem with peonies last year, spray newly emerging plants with an approved fungicide when the plants are 2 to 4 inches tall. When peonies reach 10 inches, stake or hoop them to support their blossoms. Avoid overhead watering. If fungus persists, consider relocating peonies to a more open, full-sun site. Move plants in the fall.

If weeds were a problem last year, spread a pre-emergent weed control over lawn as weather and temperature permit. Alternatively, consider hand-pulling weeds or spot-treating weeds after they emerge with a post-emergent weed control. Serious infestations often require several treatments to control the problem.