I have an African violet that was my mother’s, and I have had it now for about 25 years. The stem is gnarled and very big, but it still grows and blooms quite well. It recently developed some soft white growth on it. It usually appears at the base of a stem, but smaller ones dot the underside of the plant. It seems to be kind of sticky and it does not easily wash off. Any ideas?
— Robin B. Zollinger
Canoga Park
It sounds to me like you have mealybugs. These tiny white insects, no more than 1/4-inch in size, cluster together on stems and the undersides of leaves. They have a waxy, white covering and excrete sticky, undigested plant sap called honeydew. A common way of controlling mealybugs is to remove them with a cotton swab dipped in rubbing alcohol.
African violets bloom virtually all year. The African Violet Society of America recommends using a 20-20-20 plant food formulation, mixed with water, at half the recommended dosage. It is best to let water sit for a day before applying it to your plants.
This will allow chlorine, which is found in all of our water and burns African violet foliage, to volatilize harmlessly into the air. Water should still be kept off the hairy leaves, which become permanently stained when they get wet. Experienced African violet growers water from below.
Dishes or trays under the pots are filled with water, which then moves upward into the soil. You may have to fill the dishes or saucers several times until the soil is saturated. Water when the soil surface is dry and use lukewarm, as opposed to hot or cold, water.
African violets do best with 8 to 12 hours of ambient light but cannot tolerant direct light that will burn their leaves. East-facing morning light is best. Low light results in thin, deep green leaves, while too much light may lead to rampant leaf growth. In both cases, flowering will be minimal or nonexistent.
You can test your exposure by putting your hand between your African violet and the adjacent window with the back of your hand next to the window. If a shadow is cast, the light is sufficiently bright, but if the back of your hand heats up, then the sun is too hot for your plant and will burn its leaves.
If you have poor light in every part of your house, you will have to supply artificial lighting to induce your African violet to flower.
African violets should be repotted soon after purchase since the soil they are grown in consists almost entirely of peat moss. Peat moss is a hydrophobic material that quickly goes bone dry indoors unless it is kept in a humid greenhouse.
Repot with a mix that is 1/3 peat moss, 1/3 vermiculite and 1/3 perlite, or with a pre-packaged soil mix that is specific. Since fertilization can be as frequent as every time you water, salts quickly build up in African violet soil, which should therefore be changed at six- to 12-month intervals.
Tip of the week
African violets are easily propagated from their leaves. Detach leaves in the spring and insert them into a light soil mix, such as half-sand, half-vermiculite. Within one month, roots will begin to form from the petioles (leaf stems) and by the end of the second month, new baby leaves will emerge at the soil surface. By the end of six months, plants will be of sufficient size to be placed in pots of their own.
You can also propagate African violets at any time by dividing mature plants into two or more smaller ones.
Photo credit: BluegrassAnnie / Foter.com / CC BY-NC-SA