Margaret Lauterbach

Consider all insect control measures carefully as earwigs, squash bugs move in

Earwigs sleep in mulch during the day and then go to town on your leaves overnight.
Earwigs sleep in mulch during the day and then go to town on your leaves overnight. Statesman file

I’ve heavily mulched several beds in my vegetable garden after removing weed seedlings, so weeding chores are negligible and I can water less frequently. The downside is that earwigs are in heaven, enjoying the mulch cover. They’re busy skeletonizing leaves overnight and sleeping in mulch during the days. My dog would not tolerate sharing the yard with ducks or chickens, so applying diatomaceous earth (DE) to remaining leaves is about the only option left to me. If you use this powdery substance, do not use the DE sold for swimming pools, because that’s been heat-treated, and the tiny sharp parts of the diatom remains have been smoothed. The DE we use for insect control absorbs the waxy exterior of the insect, and the sharp points rupture the cuticles (outer layer) of the insects, together desiccating and killing the insect. DE needs to be reapplied after rains or sprinklers, though.

This is a substance you should not want to inhale, so do not apply on a windy day, and beware of getting the dust on your clothes. A gardening friend in Ireland mixes DE with water for safe spray application on leaves. When it dries, it’s effective insect control for many, she says, but not adult squash bugs. I’m about to try water spraying DE now.

Usually at this time of year I’m battling squash bugs. I may be speaking too soon, but so far I’ve found only two: one on a cucumber seedling, the other in a dill frond. I’ve found the only way I can grow squash for a reliable harvest is to grow zucchini and Zapallito del Tronco for summer squash, and butternut for winter squash, since they’re not special targets of squash bugs. Climbing zucchini usually shrugs off squash bugs too, but I’m using trellises for pole beans this year, so I’m not growing climbing zucchini. Zephyr summer squash produces such an abundance, you can usually harvest quite a lot before the squash bugs kill the plant. We can also sometimes grow Sweet Meat, Delicata and Spaghetti squash too, to harvestable size. Delicata does not keep as long as squashes such as butternut, Sweet Meat and climbing zucchini.

Special squashes such as Potimarron or Honey Roaster succumb early to the toxic bite of squash bug nymphs in my garden. I’ve tried companion planting of nasturtiums, marigolds and radishes that some say repel squash bugs, but not in my experience. One reason I may not have squash bugs in my summer bed is that adjacent to that bed (and intruding a bit) is some very strong-smelling mint. If that is the secret, I’ll report later. Mint is not a candidate for companion planting, since it’s so invasive, but it could be used to repel insects if planted in a container moved frequently to foil rooting.


Even though our summers are generally hot and dry, it’s possible to transplant plants that you now find are in the wrong place for correct sun exposure. The best time to transplant any plant is during overcast, drizzly weather, but we might have only one day like that in late July or early August. If you don’t want to wait for that occurrence, transplant in evening, water it in well, and the next morning, when your plant starts to droop, cover it with a pot or box. Don’t uncover until the day begins to cool toward evening. You may have to cover and uncover for several days until the plant is reacclimated and stops drooping.

Animal control

If you’re thinking about housing chickens or ducks for insect control, Lindarose Curtis-Bruce says ducks don’t cause as much damage in a garden as chickens do. Her ducks are gobbling all of the kale that meets their eyes, though. A movable cage, which some call a “chicken tractor,” could be used to target areas where destructive insects and slugs are most numerous.

Send garden questions to or Gardening, The Statesman, P.O. Box 40, Boise, ID 83707.