In our area, one of the most annoying insect pests is the caterpillar larva of the Tobacco or geranium budworm moth, Heliothis virescens.
This little caterpillar is usually green, but may change color to reflect the color of the petal it's eating. These pests eat petals of petunias, geraniums, nicotiana, roses and other commonly grown flowers.
One very effective control is Bacillus thuringiensis (BT), but some hesitate to use it because it will also kill the larvae of our "flying flowers," butterflies.
It's usually possible to just hand-pick the caterpillars, the smaller the better. Watch blossoms for tiny holes and/or black droppings. These larvae are most active at dusk or twilight, spending their days hiding around the base of the plant they're feeding on.
They may be controlled with Sevin, but be wary of using this product, since it kills bees. Bioneem can kill or repel the egg-laying mothers of these pests, without harming bees, ladybugs or other beneficial creatures.
THE TYPE OF POT MATTERS
Anyone can make a stab at gardening, knowing very little about it, and achieve at least a little success. As time goes on, we all learn to do things better, improving our soil, refining planting techniques and controlling disease and pests in innovative ways.
We gardeners learn something new every day.
Last week I learned another possible reason why I've lost so many citrus trees in containers. I've been blaming overwatering, but another aspect escaped my notice. A newsletter from Logee's indicates one should only grow citrus in terra cotta or unglazed clay containers, because they will let all of the soil dry out. Plastic, glazed or ceramicized pots will retain moisture around the roots, possibly causing root rot.
The faux terra cotta pots are not porous but plastic, so they too would retain moisture. A large terra cotta pot is expensive, but so are citrus trees.
APPLY MULCH GENEROUSLY
I've been growing chiles (peppers) for over 40 years, and was just told they do best if they have 5-inch-deep mulch, and infrequent watering. That deep mulch would retain moisture in the soil, permitting uptake of calcium to prevent Blossom End Rot (BER).
Janie Lamson, co-owner of Cross Country Nursery in New Jersey, suggests that deep mulch. She does a great job of growing chiles, so she's probably right, but she undoubtedly benefits from summer rains, unlike our dry climate.
If you do apply mulch, be careful to leave some unmulched area around the main stem or trunk of your plant, lest you set up conditions inviting crown rot.
Deep mulch provides cover for slugs and earwigs. Earwigs are regarded by entomologists as partly beneficial because they eat aphids, mites and nematodes. Most gardeners see their destructive side, as they eat holes in leaves, consume corn silk, eat into fruit, etc. They are hard to control, and so are slugs.
A fairly new product, approved for organic gardening and safe for pets and wildlife, is Sluggo Plus, a slug and earwig killer. This product attracts and kills snails, slugs, earwigs, pillbugs, sowbugs, and cutworms. It should be re-applied after heavy rain or lavish watering. I wonder if it would be effective if it's spread before mulch covers it, attract and kill insects when they go to hide. Follow label instructions.
It is said to be effective for four weeks. Its active ingredients are iron phosphate and Spinosad, both the mineral and the bacteria natural soil dwellers. Being of natural occurrence, insects and other pests should not develop immunity to it like they may do to synthetic chemical controls.
Send garden questions to email@example.com or Gardening, The Statesman, P.O. Box 40, Boise, ID 83707.