Many common houseplants can be propagated by cuttings from stems or leaves. (Photo courtesy of Iowa State University)
AMES – When houseplants are too large or require many plants, many of them can be propagated by plants. Plant propagation involves growing new plants from plant parts such as leaves and stems. Many species are easily propagated indoors using techniques such as stem and leaf cuttings. In this article, Iowa State University Extension and Extension horticulturists offer tips for growing your favorite houseplants.
Q. How do I propagate pothos, English ivy, or heartleaf philodendron?
Many houseplants, including pothos (Epipremnum aureum), English ivy (Hedera helix), and heartleaf philodendron (Philodendron hederaceum), do best using stem cuttings. A stem cutting is produced from the tip or part of the stem that has leaves and buds on it to produce a new plant. New roots will form from the buds on the lower part of the stem.
To take a stem cutting, cut a three- to six-inch-long stem with at least two nodes (nodes are the places on the stem where buds or leaves form). Remove the lower leaves and any flowers or fruits (if any). Although not always necessary, treating the cutting tip with a rooting hormone can help the cuttings root more quickly. Stick the cutting to a medium (perlite, coarse sand or vermiculite). Tighten rootstock around each cutting to keep it straight.
After all the cuttings have been added, water the rootstock well and place the cuttings in bright, indirect light and high humidity. A plastic dome or bag is a good way to increase humidity. Water the perlite regularly over the next several weeks to keep the root material moist. Most houseplant stem cuttings will root in three to six weeks. When the roots are 1 inch or more, plant the cuttings in a well-drained potting mix.
Q. How do I propagate African violets?
African violets (Saintpaulia ionantha) are propagated by leaves. Choose a strong, healthy leaf and cut it with a sharp knife. A 1 to 1½ inch leaf stalk (petiole) is attached to the leaf blade. Fill the pot with dry sand, vermiculite or a 50:50 mixture of perlite and sphagnum peat moss. Remove the root area and insert the cut of each leaf at an angle of 45 degrees to the center of the root. Clean the rootstock around the petiole of each leaf cut. After all the cuttings are in, pour the root wine and let it flow for a few minutes.
Next, cover the pieces with a clear plastic bag. Secure the plastic bag to the pot with tape or rubber bands. The enclosed area greatly reduces water loss from leaf clipping and prevents them from wilting and dying before they have a chance to take root. Place the jar in bright light. The roots usually form in three to four weeks. Leaves of new plants usually appear in six to eight weeks. Many plants usually form at the base of each petiole. Separate the plants by carefully pulling or cutting them. Using a well-drained potting mix, plant the plants individually in containers.
Q. How do I propagate snake plant or mother-in-law’s tongue?
The snake plant or mother-in-law’s tongue (Dracaena trifasciata, aka Sansevieria trifasciata) can be propagated by leaf cuttings. Remove leaves and cut into 3- to 4-inch-tall sections. For each section, the area closest to the base of the parent plant is at the bottom and the furthest is at the top.
To help you remember which end is which, cut the tip of your cutting at an angle or with a step above so that the leaf parts don’t root upwards. Dip the lower end of each section in rooting hormone and then insert one to two inches deep into a moist rooting medium (perlite, dry sand, or vermiculite). Keep the root system moist by watering regularly. In three to five weeks, new roots will form and sprouts should appear in two months.
Q. Can I submerge houseplants in a glass of water?
Many stems and leaves are easily rooted in a glass of water. While many types of houseplants can easily root in water, the roots they develop are coarser in texture and not suitable for growing in regular clay soil. This means that once water-rooted cuttings are planted in clay soil, they often show signs of stress, such as wilting, leaf drop, leaf browning or tip dying. Providing good constant care will help the small propagules to recover after planting.
If water is used, change the water frequently (one to two times per week) and never allow the water level to drop and expose the growing roots to air. When the roots are about an inch long, transplant the cuttings into potting soil.