In Repotting, Big Usually Not the Best
QUESTION: We want to repot some of our house plants and would like to shift to a much larger pots so we won’t have to repot them more often. Is that a good idea?
ANSWER: Don’t fall for the mistaken notion that shifting the plant into an extra large pot is best for the plants. Shift the plant into a slightly larger pot (next size larger is ok), never more than a 2-inch space between the root ball and container wall.
Why no larger? Potting soil in an oversize pot can stay too wet and get musty when out of reach of roots for a very long time. Toxic substances build up and damage the plants.
Pots made of clay evaporate 50% of the water you give them directly through its walls. But glazed clay pots and plastic types lose no water through the wall. That means you should cut in half the number of times you need to water plastic or glazed types.
Don’t Use Kitty Litter Near Food Crops
Q: We use a granular clay kitty litter and wonder if it can be used on the compost pile or in the garden?
A: It’s not a good idea to use spent kitty litter anywhere near food crops because of possible disease infection. There’s no reason why it can’t be used as a mulch around trees and shrubs.
Treated Lumber Not Good for Birdhouses
Q: I made a birdhouse and feeder out of treated lumber. My neighbor said it is a no-no because the lumber gives off a toxic material harmful to birds. Is that true?
A: Your neighbor is right. We checked this with the Cornell University laboratory of ornithology and they do not recommend making feeders or nest boxes from treated lumber.
They concluded that “most wood preservatives are toxic to birds.” Besides, pressure-treated lumber is expensive, and people are more likely to take the time to build these structures if they can be built inexpensively. They suggest using rough-grade lumber.
Use Warmer Water to Mist African Violets
Q: A friend of mine mists the leaves of her African violets and it seems to help them. I’ve put water on the leaves and it injured the plants. Does misting harm foliage?
A: Many fanciers mist their African violets, and it’s safe if you use water the same temperature as your room. If water is 10 degrees colder than room temperature, misting will cause spotting, especially in strong natural light.
You can prevent this by drawing off a container of water at night and letting it set until the next day when it is used for misting. Also, this allows the chlorine to dissipate.
Pests Ate Leaves of Tomato Plants
Q: Last year, our tomato vines were nice and green, but they developed a few fat, green cigar-shaped worms which ate the leaves. The pests had some small white, oval-shaped structures on their backs. Several worms died. Did the white things have something to so with this?
A: You had tomato hornworms that were attacked by braconid wasps, a natural parasite that lays eggs in the hornworms. The eggs hatch inside, eat their way out and form cocoons (the small white things), which in turn hatch out and move to other hornworms.
If you do not have these predators, you can spray bacillus thurlingiensis on the worms. Garden stores may have it under names such as Di-pel, Thuricide and other trade names. Look for the scientific name on labels of organic pesticides. It is effective against cabbage worms as well.
The Abrahams cannot answer questions individually, those of general interest will be addressed in this column. Write to Doc and Katy Abraham, Los Angeles Times, P.O. Box 579, Naples, N.Y. 14512.
