Grasshoppers have eaten all my spinach and collard seedlings. I want these critters gone! Grasshoppers lay eggs in undisturbed sites (ditches, weedy areas, waysides, etc) in late summer and fall. They lay from two to 120 eggs, which survive the winter. They begin hatching in April and May and peak in mid-June. Cool and dry springs can delay hatching until June and July. Hatching can take three to four weeks. The young become adults in nine to 11 weeks. Active feeding can occur over an entire growing season.
Although it may not seem true to those of us whose gardens have fallen victim to grasshopper predation, grasshoppers are careful in their food selection. They actually sample potential food sources before choosing one over another.
Grasshoppers are least active in the early morning before the temperatures rise. This is a good time to catch and kill them. I have caught many by hand and stepped on them to crush them. A sweep net to remove them from vegetable and flowers also works.
Digging and cultivating in early spring make the eggs available for predators and exposes them to freezing, thawing and dehydration. Tilling vacant land in mid- to late summer reduces potential egg-laying sites. Keeping waste areas, fence rows, roadsides, and other egg laying ground free of weeds through cultivation or herbicide treatment may discourage egg laying, since eggs are laid where nymphs are most likely to find food readily available the following year.
Two feet tall barriers can help keep grasshoppers out of gardens. These must have a smooth surface because grasshoppers are great climbers. Angling the barrier away from the garden makes it even harder to climb. There must be no entrance holes, even at the soil. Floating row covers will also protect vegetables and ornamentals. These have to be secured well so critters can’t get in at the soil level. Be aware that grasshoppers can chew through lightweight products!
Sticky yellow traps attract grasshoppers. Jars, shallow pans and buckets filled with a ten percent solution of molasses and water can trap grasshoppers. Cover the liquid in the containers with a film of canola oil to deter bees and mosquitoes. Bury the containers so that the rims are at ground level for the best results. Remove the dead grasshoppers daily. Clean the trap and renew the bait as necessary.
Nest year, I will start my seedlings indoors and plant them out when they are big enough to resist the grasshoppers.
On September 20, from 6 p.m. to 8 p.m. at 2621 Northgate #12, Cooperative Extension will offer a free class, GETTING STARTED. Learn about site location and planning, what to grow, cultivar selection, planting dates and three season gardening.