2018 Garden Recap: Vegetables (Part 1) (aka Attack of the Squash Vine Borer)

In my last post, I wrote about how my flower gardens fared this year. Next up is the vegetable gardens.

In a word, this year the vegetables gardens were a disaster. Not for any one reason, just a lot off bad things conspired to really take a toll and make it one of the worst years I’ve ever had gardening. Makes me long for the days when I gardened in New Jersey and everything just grew lush and beautifully. Except for the year I had hornworms on the tomatoes. Those were disgusting.

Back in the spring, I was so hopeful for a summer of fresh vegetables. But that was not to be. The squash and zucchini was looking great through early July. I was getting tasty Emerald Delight Zucchini (Botanical Interests) and Gold Hybrid Gourmet Gold (Burpee), and the vines were covered in flowers.

Then over about a week in early July, they just up and died.

I thought it was powdery mildew, but it was so dramatic. I’ve had plenty of powdery mildew and it didn’t really look like it. I pulled it all out and threw it into a garden waste bag (you don’t want diseased plants hanging around your yard). Didn’t think much of until I was writing this post and wondered what had really happened. As soon as I started doing some investigating, it quickly it became quite obvious from the pictures that mine had been attacked by squash vine borers, not powdery mildew.

All that orange mess around the base of the plant is a moist orange sawdust-like material called frass, or insect droppings. It was everywhere. Yuck. That is a sign that the squash vine borer larvae is eating away at the material inside the stems of the plants. I never looked close enough to see them, but the evidence was pretty overwhelming. Here’s photos of the adult and larvae (Photo credit to the UMN Extension)

So what to do now? Obviously I totally lost this year’s crops, but how do I prevent this from happening again?

First off, I need to be better about practicing crop rotation. I pretty much never rotate crops to different garden areas, but obviously I need to be better about that. Squash vine borers spend the winter in the soil near their recently infected host plants, so I need to have next years plants as far away as possible.

Then, according to the UMN Extension, I will need to check for adult squash vine borers starting the end of June. I’m not sure if I’ve ever seen them, but I will be on the lookout after this. You can also try to use some kind of container filled with water with yellow food coloring added to attract and trap them.  Check each day to see if you’ve trapped any.

If you do find the squash vine borers in the area you’ll need to change things up a bit. Easiest is to practice crop rotation. You can also try planting other crops that aren’t as susceptible like butternut squash, cucumbers, melons and watermelons. Although none of them are really substitutes for summer squash and zucchini.

Try planting a second planting in early July after any adult borers have finished laying eggs on the mature plants. But, this is tough in the northern climates that already have a short growing season.

Try using a physical barrier.  Wrap a collar of aluminum foil around lower stems to prevent egg-laying. Alternatively, secure floating light fabric row covers over your squash until they start to flower. Don’t use row covers if the infected squash plants were planted in the same area as the previous year. This is because squash vine borers spend the winter in the soil near their host plants. When the adults emerge the following summer, they may be trapped under the row cover instead of being kept out.

Hopefully this was a one time event and I can go back to having way too much squash and zucchini for one family to eat. Whenever something like this happens, it really makes me appreciate the organic farmers who grow on a large scale and how precarious each year’s crop is. At least I can just pack it in for the year and go to my local farmer’s market.

There’s a lot more good information on how to deal with these pests at these sites:

• University of Minnesota Extension
• University of Maryland Extension
• The Old Farmer’s Almanac
• Missouri Botanical Garden

I would like give a shout to the land-grant University Extensions and their educational and problem-solving assistance they provide to the public. These community outreach programs provide invaluable scientific knowledge and expertise on a variety of topics. I’ve watched a number of webinars on gardening topics from the University of Illinois Extension and have found them to be really interesting, useful and free!

Have you ever had a whole crop wiped out like this?

Next post will look at the rest of the vegetable garden–stay tuned!