Things You'll Need
General purpose potting soil
Garden shears or a sharp knife
Spray bottle or mister
Be patient. Do not test the roots of Lobelia cuttings until they have been in the soil for at least two weeks.
Lobelia cuttings must be kept moist, but moisture makes them subject to fungus. If you see fungus on your cuttings throw them out and start again.
Lobelia is a dependable perennial that is a favorite of gardeners due to its showy flowers and its ability to attract butterflies and hummingbirds. Some varieties are native to the United States and others have been cultivated to thrive in our gardens. Varieties of Lobelia available at gardening centers are generally inexpensive, but propagating Lobelia from cuttings can stretch garden budgets even further. Lobelia can also be grown from seeds, and clumps of the perennial can be divided to create new plants.
Cut Lobelia in the late spring.
Cut only pieces of new growth that have not yet flowered. "Flowers are the tip-off: Flowering growth is mature growth," explains horticulture expert Kenneth W. Mudge, Ph.D. A cutting should have three to four growth nodes (the tiny buds on the stem where new leaves emerge). Remove any leaves from cuttings. Use your garden shears to cut several 4 to 5-inch pieces of stem growth from the donor Lobelia plant.
Fill the clay pot with potting soil. Water the potting soil.
Push cuttings into the wet soil. Leave approximately half of the cuttings above the soil. For the cuttings to support their own weight they must be submerged at least half way.
Place your pot of cuttings in a shady area protected from wind and animal pests.
Mist your cuttings twice a day with water. Water the pot every other day. Cuttings will not set unless they are kept in a constantly moist environment.
Replant your cuttings when roots have set. A new plant is ready for transplant when it has healthy foliage growing above the soil and strongly resists if it is gently tugged. Its resistance to pulling indicates the presence of new roots.
Garnet Greene has written professionally since 2004. Her expertise includes gems and jewelry, home improvement, gardening, cooking, decorating, fashion and entertainment. Greene writes for Answerbag, Daily Puppy, eHow, Firefox.org, Garden Guides, Garden Inspirations, So You Wanna, and the print magazine "Engagement 101." She has a bachelor's degree in English literature and is a formally trained screenwriter.