Natural Controls in the Garden

Natural Controls

There are many non-chemical means of dealing with cucumber beetles and squash bugs, so you shouldn't have to resort to the use of chemicals, no matter what their level of toxicity. Here are some natural remedies that we have heard about.

You can use predator insects, such as tachnid flies, parasitic nematodes and braconid wasps, or lacewings and ladybugs, which eat the eggs. (Note that Sevin kills some of these beneficial insects!) Bats are also predators of cucumber beetles (among other pests), so build a bat house near your garden. Companion planting has also proven effective in controlling cucumber and squash bugs. Try interplanting with broccoli, radishes, beans, catnip, goldenrod, nasturtiums, calendula or tansy. If you have a relatively small garden, try hand-picking the critters. Or a friend of ours effectively used a portable vacuum cleaner to suck up the adults in the evening.

Or trap the beetles. Cut a piece of plywood or cardboard into eight-by- ten-inch pieces. Paint the board yellow and coat with Tanglefoot or some other adhesive. Bait these traps with allspice oil or clove oil and stake them vertically at or near ground level. However you gather the beetles, be sure to dispose of them quickly.

Deep mulching with straw around the plants will make it difficult for the bugs to migrate from plant to plant and deter them from laying their eggs in the ground near plant stems. Cover the mulch with onion skins and they will be further repelled.

Mix a spray of one ounce of wood ashes, one ounce of hydrated lime and one gallon of water. Spray both upper and lower leaf surfaces. Or use a spray of hot peppers, water and garlic. Another trick is to flatten a square of aluminum foil or an aluminum pie plate around the base of cucumber plants. This will bounce light onto the undersides of leaves and confuse the beetles enough to keep them at bay.

If the infestation gets out of hand, there are botanical insecticides like pyrethrum and rotenone. There is research that suggests the use of neem oil applied to the soil at the right time will destroy eggs and larvae. A kaolin clay product is also available to used as a foliar spray. It creates a non-toxic particle film that places a barrier between a pest and its host plant and also has reflective properties that disguise the plant, similarly to aluminum foil.

So help preserve the biodiversity in your neighborhood and stay away from Sevin and its ilk.