Vegetable garden issues

Editor’s note: This article is from the archives of the MSU Crop Advisory Team Alerts. Check the label of any pesticide referenced to ensure your use is included.

August is a great time of the year for those of us who grow vegetables in backyard gardens. Our hard work during the spring and early summer is paying off with fresh cucumbers, basil, parsley, summer squash and if our nights ever warm up, tasty tomatoes. The following are some of the pest and disease issues I am seeing in my garden, maybe this will help identify similar problems in your garden.

Holey peppers
Holely peppers. Photo credit: H. Russell, Diagnostic Services.

European corn borer injury to peppers

This ubiquitous caterpillar bores in the stems and fruit of many plants. I get them in peppers and tomatoes as well as my sweet corn. Once you see the damage, there is not much you can do about it. I tend not worry about the minor damage this bug does; I just toss the fruit and move on.

european corn borer
A line of small holes across sweet corn
leaves shows where a European corn borer
was feeding in the whole ear.
Photo credit: H. Russell, Diagnostic Services.

squash leaf disease
Squash leaf disease.
Photo credit: H. Russell, Diagnostic Services.

Powdery mildew and squash and cucumbers

White blotchy patches on yellowing leaves are the signs of powdery mildew. I battle this problem every year and have lost most of these battles. Powdery mildew can result in total decline of the affected plants. Religious pruning and fungicide sprays have kept this disease at bay this year.

bad looking basil
Bad looking basil.
Photo credit: H. Russell, Diagnostic Services.

basil roots rhizoctonia
Basil roots rhizoctonia.
Photo credit: J. Byrne, Diagnostic Services.

Rhizoctonia root rot in basil

I found one sorry looking basil plant (see arrow in photo) among a row of healthy, vigorously growing basil plants. I brought the whole plant into the lab, and Jan and Jackie isolated rhizoctonia rot root. Hopefully, this fungal pathogen won’t spread to the other basil plants. The dark diseased looking root is a dead give away of root rot.

sorry looking parsely
Sorry looking parsely.
Photo credit: H. Russell, Diagnostic Services.

parsely crown borer
Parsely crown borer
Photo credit: J. Byrne, Diagnostic Services.

Parsley crown borer

I thought I had a root rot problem in my flat leaf parsley too, but when I looked closer I saw that some bug had chewed out the center of the crown. I didn’t find the bug, so I don’t know what did it. Remarkably, the parsley recovered and began to produce new shoots. Too bad I dug it up.

Japanese beetles

I see them all over the garden. They chew a little bit here and there, but mostly I just see them copulating.

Japanese beetles on sweet corn
Japanese beetle on sweet corn.
Photo credit: H. Russell, Diagnostic Services.

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