From the Gardens Registrar: What’s Eating Your Plants? Potato Beetles? Flea Beetles? Cucumber Beetles? Turkeys?; This Weekend’s Workday – To Be Announced Separately

Hello Gardeners,

Now that it’s really summer, we have a great many insects in the gardens, including big, beautiful Monarch and Swallowtail Butterflies. Unfortunately, some of the insects are attacking our plants. Here are a few of them:

POTATO BEETLES – Reports are coming in from all around the gardens of the appearance of potato beetles – eggs, larvae, and adults. These eat, of course, potato plants, but also other plants in the nightshade family, including tomatoes, eggplants, and peppers. We will probably spray Spinosad in the garden in a week or two. This is an insecticide that is acceptable in organic gardening. We are very careful with it, because it is harmful to bees, so we will spray in the evening around sunset when the bees are inactive. We’ll also try to avoid spraying potato blossoms. We will need dry weather to spray, since Spinosad breaks down very quickly. Here’s a website with good information and pictures: https://www.extension.umn.edu/garden/insects/find/colorado-potato-beetles/

FLEA BEETLES – Flea beetles are an annoying pest that attack young plants and put holes in the leaves. They are most active early in the season. The beetles are tiny (about 1/16 of an inch), shiny and black. They eat lots of different vegetables, but members of the cabbage family seem to suffer most from their visits. The beetles, of course, weaken the plants, but most seedlings will survive, and once the plants mature, the beetles will gradually go away. Some possible remedies to help your seedlings survive attack until they’re big enough to fend for themselves are sprinkling coffee grounds around the seedlings, or spraying the plants with soapy water. Some people get good results from grinding up eggshells and sprinkling those around the seedlings. Talcum powder sprinkled on the plans is also said to be effective. (I haven’t tried any of these.)

CUCUMBER BEETLES – There are also reports of cucumber beetles in our gardens. These are rather handsome beetles with black and yellow stripes (not too different from the potato beetles.) There are also spotted varieties, but I have never seen them in this area. They eat plants of cucumbers and their relatives, including squash and melons. Their chewing wouldn’t do much damage, but unfortunately, they spread bacterial wilt, which is usually fatal to the plants. Row covers are very helpful in protecting the plants, and planting radishes and nasturtium nearby might be helpful in repelling the insects. Mulch may also make the plants less attractive to the beetles. Here’s the University of Minnesota Extension website again: http://www.extension.umn.edu/garden/insects/find/cucumber-beetles-in-vegetable-gardens/

With the larger beetles, monitoring your plants carefully, and hand-picking the beetles off of the plants is the cheapest, safest, and most effective way to protect your plants.

TURKEYS – Not all garden pests are insects. One gardener has reported considerable damage by turkeys eating his seedlings. Another gardener reports not being able to weed all of her plot because a turkey is nesting in her garden. Please note, hand-picking of turkeys is not advisable. 

WORKDAY – I’ll send out a separate email about this week’s workday.

Happy gardening,

Kathryn