The Sauk County Gardener— Insects and Other Bugs to Watch for in the Garden

Jeannie Manis, Sauk County Master Gardeners Association (SCMGA) President

“We must remain as close to the flowers, the grass, and the butterflies as the child is who is not yet so much taller than they are.” -Friedrich Nietzsche

Last week I wrote about the proper way to water your garden and now I am listening blissfully to a nice gentle rain as I write this article. Maybe I should have written about watering earlier. At least with some rain, I won’t have to use my gardening time to water. Instead, I will get to work on some much-needed gardening tasks.

As we near the end of June/first week of July, there is a lot going on in the gardens. I spotted four
monarch caterpillars on my milkweed. I always leave some plants near the back of my flower beds for
them. I’m always excited to see them and I can’t wait to show them to my grandson when he comes
this week. If you have some milkweed near or in your garden, avoid pulling it or using pesticides or
insecticides in the area.

Photo via Jeannie Manis

On a not-so-happy note, I believe I spotted cabbage moths flying around so it is time to start watching my cole crops – cabbage, broccoli, Brussels sprouts, and cauliflower for cabbage moth eggs. The eggs look like look like white or yellow oblong dots and usually are attached to the underside of leaves. If you spot them, squishing them is a great way to control them early. Another option is to use row covers. Later if the eggs hatch and you have to deal with the caterpillars, you’ll have to resort to handpicking or using Bt (Bacillus thuringiensis var Kurstaki or Aisawai). Bt only kills the larvae of moths and butterflies and is safe for other insects, wildlife and humans.

While you are in the vegetable garden, check your tomato plants to see if they need pruning. I pruned all mine this past weekend. Pruning increases air flow and removes leaves that touch the soil; all which can help minimize the damage from diseases such as septoria leaf spot, early blight and bacterial spot. When pruning, remove any leaves that would touch the soil and remove any suckers. Also tie up the tomato plants as they grow. If you haven’t already, mulch under those tomato plants to help reduce splash up when it rains or when you water and to retain as much moisture as possible.

June is when the dreaded squash vine borer visits the garden. When I lived in Missouri, these did a number on my zucchini and other squash. Watch for an orange and black, day-flying moth near your
vine crops. They lay their eggs at the base of the vine. Check the base closely and look for any eggs;
smash any that you find. If you see any sawdust looking material at the base of your vines, the borer
has already entered your vines. You can slice the vines open lengthwise and remove any bores that
you find. Then bury the vine, water to keep the soil moist, and hopefully the vine will develop new
roots. It worked for me in Missouri; I’m hoping I won’t have to deal with them this year.

A lot is going on in the flower gardens as well. I started a shade garden about three years ago and it is starting to really fill in. This past weekend my daughter and her best friend since kindergarten came out to help me move some plants and they spotted some slugs. There are a couple ways to control slugs. You can place boards in your garden or put small, shallow containers of beer around your hostas and other slug-susceptible plants. If you use beer, the slugs will crawl into the containers and drown. If you put down boards, they’ll crawl underneath during the night. Come morning, you can turn over the boards and destroy them. I don’t share my beer, so I’ll just have to put down a few boards. Start watching for Japanese beetle scouts and be prepared to destroy them. They’ll be showing up soon and if you stop the scouts from telling the rest of their buddies about your garden, the better off you’ll be. I’ve never been successful, but I keep trying. Of course, at this time you may need to do some weeding your gardens. The best way to keep weeds down in the vegetable garden is to mulch. I have raised garden beds so it’s easy for me to mulch. If you haven’t already added some mulch, weed and then immediately add some mulch for what you’ve just weeded. My flower beds always need some weeding and I have any awesome way to do it. I always have plants that need dividing or I’ve purchased some to put in my beds; so I find a “weedy spot”, weed it, and then put in my new plant. I like to think I’m extra efficient as I do some weeding and planting at the same time. Overall, it is a great time to be gardening in Sauk County.

This week’s article is written by Jeannie Manis, a Wisconsin Certified Sauk County Master Gardener Volunteer. If you have any gardening questions, please contact the Extension Sauk County by emailing or calling the University of Wisconsin Madison Division of Extension Sauk County office at 608-355-3250.