Issue: January 6, 2007
African violet problems
Question:
I have had problems with my African violets. They were looking good, and then the leaves started wilting. I watered them, but they didn't recover. They just continued wilting and then the leaves started dying. What's wrong?
Answer:
As usual, there are several potential problems. The first thing to consider is insect attack. Cottony mealy bugs can cause this problem. These are small insects that suck the juices from plants. They cover themselves with a white waxy material that looks like fluffy cotton. If you see what appear to be small cottony masses on the base of the plant, on the leaf petioles, or on the undersides of the leaves, this may be the problem. They may be treated in several ways. Insecticidal soap sprayed onto the insects should help. Malathion or other insecticides may be used if you can take your plants outside to apply the chemicals and leave them outside until the chemical has dried. Be sure to follow the directions on the label if you use any chemical (organic or not). Some people apply insecticidal soap or even stronger insecticides with a cotton swab to minimize spraying and directly target the pests. Wear disposable gloves if you use this method. Inspect your plants again after a week to see if the insects have reinfested from eggs that were not killed by the treatment. If the insects reappear, you must retreat. It is often advised to treat 3 times, 3 to 4 days apart, to be sure that no insects can hatch, mature, and lay eggs to continue infestations.
Another consideration is salt accumulation from irrigation water and fertilizers. If the plants have not been repotted for a while, this may be the culprit. In this case you will probably see a brownish to white deposit on the top of the potting soil as it dries, or on the pot in which the plant is growing. The solution to this problem is to remove the plant from the pot gently tease as much of the old soil off the roots as possible (minimize damage to roots, but don't worry if some roots are broken). Healthy white roots that are apparent at this time are a good sign. Repot the plant in new potting soil and water it just enough to settle the soil. In subsequent waterings, water enough to allow water to drain from the drainage holes in the pot, but don't let this drained water reabsorb into the soil. This drainage water (or leachate) carries salts from the soil so you don't want it returning the salt to the soil. Discard this drained water.
Finally, if you were busy and allowed your plants to dry excessively, then watered heavily, you may have caused development of root rot disease. If the plant is not too severely damaged, it may be possible to restore the plant by repotting it as described above. It is always a great joy to see a plant that has declined return to vigorous growth and bloom. This is one of the joys of winter gardening indoors.
Marisa Y. Thompson, PhD, is the Extension Horticulture Specialist, in the Department of Extension Plant Sciences at the New Mexico State University Los Lunas Agricultural Science Center, email: desertblooms@nmsu.edu, office: 505-865-7340, ext. 113.
For more gardening information, visit the NMSU Extension Horticulture page at Desert Blooms and the NMSU Horticulture Publications page.
Send gardening questions to Southwest Yard and Garden - Attn: Dr. Marisa Thompson at desertblooms@nmsu.edu, or at the Desert Blooms Facebook.
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