× Citrofortunella mitis is commonly known as calamondin orange, and as the "×" in front of the genus name denotes, it is a hybrid between species in two different genera, an oddity in the plant world. Citrus reticulata (a tangerine) was crossed with Fortunella margarita (the Nagami kumquat) to create a small fruited hybrid with a loose skin and very bitter pulp, whose juice can be used like lemon or lime juice. This hybrid of Philippine origin can survive a few degrees of frost, which is why it is featured in the Semitropical Greenhouse.

All types of citrus grow best in full sun and warm temperatures. Flowers are typically pollinated by honey bees, and the resulting orange blossom-scented honey is highly prized. Somewhat drought-tolerant once established, calamondin oranges will need frequent watering if grown in containers.