How to Grow Alternanthera Plants
Description: A tropical and tender perennial, the Calico Plant is treated as an annual and grown for its brightly colored leaves. They come in a wide range of showy shades: red, green, pink, copper, purple, and yellow. The broad, oval leaves may also be marked with blotches of orange, red, or yellow and look similar to coleus. In late fall, check for white flowers, set on short stalks; they are small and hard to see. A compact, fast-growing annual plant, the Alternanthera (all-ter-NAN-ther-ah) has been a landscaper’s favorite for centuries. The small mounds and showy colors were used in English knot gardens and even inspired Victorian needlework designs. This exotic plant is also used as a medicinal in Africa, India, and Taiwan. There are nearly 200 different types of Joyweed growing all across the U.S. and around the world. In some places, it’s called an invasive weed.
USDA Hardiness Zones: Winter hardy in Zones 10-11.
Growth and Shape: Plant 4 to 9 in. apart for ground cover; can also be used to edge the lawn. Since Joseph’s Coat grows quickly, you’ll need to pinch off stems or trim with shears to keep the compact, mounded shape.
Maintenance: Alternanthera plants need a rich, organic soil that drains well and is kept moist. Full sun develops the best colors, although it can stand partial shade.
Fertilizer Needs: Liquid fertilizer every 2-3 weeks or granular once a month; granular needs water to activate it. Follow directions on container.
Propagation: From seed: start Alternanthera seeds indoors in late winter and transplant outdoors after last frost. Check seed packet for directions. Stem tip cuttings may be done in late summer. Order live Alternanthera plants for the more popular varieties if you choose not to bother with the seed or the cuttings.
Display Tips: For a tropical garden, start with some elephant ears, cannas, or caladiums to contrast with your alternanthera annual plants. If a cottage garden is more to your liking, try Black-eyed Susans, shasta daisies, purple coneflower, or blue salvia alongside your Joseph’s Coat. “Purple Knight” Alternanthera looks nice with Tidal Wave Petunia, New Gold Lantana, or the French Dwarf Marigold Bonanza. This tropical perennial also makes a striking accent plant grown in a container.