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How to Care for Alternanthera

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Alternanthera is highly praised for its colorful leaves and design. Known to gardeners as “Joseph’s coat,” the Alternanthera is a genus of around 80 different herbaceous plants in the amaranth family. Most commonly used as a ground cover, Alternanthera can be grown year-round if you live in planting zones 10 and 11 (very warm climates); however, in other areas Alternanthera is grown as an annual.

Disturb the ground by digging, loosening and breaking apart any clumps. Use a spade shovel or a power tiller.

Apply compost to the planting area and mix in with the dirt using your shovel. Spray the mixture with just enough water to moisten the area.

Cover the planting are with black plastic sheeting and allow it to set for a day, then remove for planting. The heat attracted to the black plastic sheeting will "cook" the compost, allowing it to release nutrients into the ground that are beneficial for the plant.

Plant the Alternanthera during late spring, in an area that receives full sun for most of the day. The area should not pool water, but have well-drained soil.

Fertilize the plant once per month with an all-in-one fertilizer to promote best growth. Apply the fertilizer throughout the growing season until the first frost of winter, according to the package instructions.

Prune the Alternanthera plant using sharp pruning shears as needed, to do away with any dead or dying foliage or to just shape the plant.

Remove the plants from the ground after the first frost of winter and discard them into a compost bin for next year. The Alternanthera cannot survive winter conditions, and new plants will need to be planted the next year.

Propagation Of Alternanthera

Alternanthera is a large genus incorporating 200 species of bushy annuals and perennials that are grown mainly for their attractive colorful leaves. Ripe seeds are removed from within the flowers of alternanthera plants for early spring propagation. Alternanthera dentata 'Purple Knight' and Alternanthera ficoidea 'Red Threads' both germinate in moderately cool temperatures, about 55 to 64 degrees Fahrenheit. It is best to plant young and fully developed specimens outdoors when frost is past. Soil should be moist and well-draining, and the location should receive plenty of warmth and full sun or part shade. The ruby foliage of Purple Knights makes it ideal as a colorful potted, edging or ground cover specimen. The burgundy colors of the mounding Alternanthera ficoidea 'Red Threads' plant make it stand out in the garden, where it can be planted in groups.

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