DEAR JESSICA: Look what came to dinner! I don’t know what this is but it truly is amazing to see.
— Linda Matejka,
DEAR LINDA: That’s a tomato hornworm (Manduca quinquemaculata). Found throughout the United States, the destructive pest targets not only tomatoes, but also eggplants, peppers and potatoes, all members of the Solanaceae, or nightshade, family. And they shouldn’t be ignored because they will cocoon and overwinter in the soil, and return to destroy your plants next year.
The caterpillar, easily identified by its hornlike appendage, and seven diagonal stripes accented with brown dots, can grow as long as three to five inches, but fear not: that scary-looking horn poses no threat to humans. Your plants, on the other hand, are in imminent danger and need to be saved. Hornworms can defoliate entire plants in as little as a day.
The easiest way to get rid of the pests is to remove them by hand, then drop them in a bucket of soapy water and they’ll drown. If there are too many to control by hand, apply bT, a natural, bacteria-based pesticide available at most nurseries, to plants, following package directions.
The only hornworms you shouldn’t target are those that appear to be covered with rice. Those are parasitic wasp larvae, and they’re doing the job for you.
When you clean out your garden bed in the fall, till the soil to disrupt any pupating caterpillars. Do so again in early spring and repeat a third time before planting. This practice has been found to be very effective in diminishing, and even eradicating, the population.
Next year, interplant marigolds with your tomatoes, peppers, eggplants and potatoes. They’ll repel the pests naturally.
DEAR JESSICA: I wonder if you can help me identify this insect that has been digging holes in my yard and leaving mounds of dirt. I thought it was a mud wasp, but am not sure.
— Ed Korn,
DEAR ED: That’s a cicada killer wasp (Sphecius speciosus). As their name implies, adult female wasps attack cicadas, stinging them and injecting a paralyzing venom. With the cicada immobilized, the wasp carries it to a prepared burrow and lays eggs on its body. When the eggs hatch, larvae emerge and feed on the cicada. It’s like a scene straight out of a horror movie.
The good news is that, as threatening as their 2-inch-long, shiny bodies may appear, they don’t typically sting people unless threatened. There really isn’t any call for control, but if you’re bothered by the holes in your yard, wait until dark and pour some boiling water into each hole to kill them off.
DEAR JESSICA: I have large spaghetti squash in my garden that aren’t turning yellow. They are out in the sun; meanwhile, on the opposite side of my garden I found ripe smaller ones. I thought sun was needed to turn the squash yellow. So why are the hidden ones ripe and the exposed ones not ripe? They’ve been like this for a couple of weeks.
— Kristina Prunitis,
DEAR KRISTINA: The reason that plants on opposite sides of your garden are producing different-looking squash is because they are different plants. The green one is called Stripetti squash (Cucurbita pepo, Stripetti), and it’s never going to turn yellow; the color of the fruit in your photo is its mature shade.
Stripetti, a hybrid of Delicata and spaghetti squash, is a winter squash valued for its long shelf life.