Asparagus fern is a popular houseplant in the U.S. It is grown as a drought-tolerant landscape plant in USDA horticultural zones 8 through 10. It is evergreen in zones 9 and 10 and root hardy in zone 8, meaning it dies to the ground in the winter. Asparagus fern has arching stems that stretch out from 2- to 6-feet long with thin, prickly leaves. The roots create a mat that contain numerous woody bulbs that store water and nutrients. Asparagus fern is native to South Africa and has escaped cultivation and is considered a weedy pest in some parts of Southern Florida. However, it is used as a durable houseplant in most parts of the U.S.
Plant the asparagus fern in a well-drained container that has a 2-inch space between the side of the container and the root mass. More than 2 inches of unused potting soil can remain damp and begin to rot as the organic matter decomposes, causing bad odors. Plant the fern slightly deeper than in the previous pot so all the roots are covered. The root mass of the asparagus fern is very dense. Do not try to separate or disturb the root mass unless you are making root divisions for new plants.
Water the asparagus fern when the top inch of soil in the container is dry. Check the moisture level by pushing your finger into the top inch of soil. Add water until it drains out of the bottom of the container. If the leaves begin to yellow, then you are giving it too much water. If water cannot drain from the bottom of the container, then it is time to plant the asparagus fern into a new pot because it is root bound.
Place the asparagus fern in the brightest place possible in the home without being in direct sun. The plant will suffer and the leaves will lose color if the plant is located in excessive shade. Direct sun, however, causes the plant to dry out rapidly and lose vigor.
Fertilize with a half-strength, water-soluble fertilizer for houseplants every other time you add water to the asparagus fern.
Trim off dead fronds or branches if they turn yellow or decline from old age. Asparagus ferns can be cut to ground level and allowed to regrow into an even, full shape. However, they grow slowly and it may take a year for them to regain their size.