Many gardeners in the region are anxious about planting winter squashes this year, given that last year, we spent hours and hours removing hundreds of squash bugs from our plants before they had a chance to fruit. This season, we’re going in with a series of strategies to increase our chances of success.
We owe a big thanks to Katie Batazzo of Front Yard Fresh for hosting a Squash Bug Strategies workshop at Edwards Greenhouse & Flowershop on May 6th, and to Sierra Laverty, the Idaho Plant Doctor, for researching squash bugs last season and sharing notes and strategies with us.
Article by Mary K, Marketing Manager, Community Outreach and Education Coordinator
Firstly, let's define what squash bugs are and what they look like. Squash bugs are a major pest of squash in our area. They lay eggs on the underside of leaves, which suck the juices from the leaves. Over several weeks, they can cause the plant to become shriveled, yellow, and eventually die. Read on for more more information from Wikipedia. Our growing season is short enough that we may not see the full host of issues here.
Life Cycle of the Squash Bug
The adult squash bugs that do the wild mating dance on your plants survive over the winter. They have been lying in wait for those delectable tender young squash plants so they can feast and propagate. Each female lays between 300-400 eggs, which suck the juice from the plant under the leaves. Hatching occurs in 1-2 weeks, and then come the nymphs, which are small, gray, and fast-developing. In 1-2 weeks, they become adults. From there, they will either stay and feast on the remains of the squash or fly off to seek new squash to take over.
The theory is that last season was such a long, hot one that there was enough time for two generations of them to get established. This means there could be a ridiculous number of them to contend with this season. You could be dealing with about 100 bugs per vine.
We anticipate the return of increasingly warm temperatures next week, which means that squash bugs will begin appearing soon. Some gardeners have already reported sightings. When you spot them, pick them off and drop them in a bucket of soapy water. A soap that has grease-fighting abilities works well, like Dawn. Don’t squish them, as it releases a scent that attracts more of them. Keep a lookout starting this week. We know that the first couple of weeks in June last year were an active time for them. Don’t wait until the first week of July to begin dealing with them, as they will be well established by then.
Here are several strategies that you can use. Pick and choose the ones that suit you best, and keep notes!
Trap Them
If you have the space, plant a trap crop two weeks before you plant the crop you’re hoping for. The goal is to lure the squash bugs to an area where you can deal with them and grow your squash in a place where you can more strategically prevent them from attacking.
The key is to allow for space between the trap crop and your squash crop. Plant them on opposite sides of the yard or in containers located in different areas of your growing space. Plant the trap crop where you had trouble last season, and provide regular water and a little bit of food to get the plant going.
Some suggested trap crops are:
- Hubbard Squash
- Yellow Crookneck Squash
- Some have also seen the bugs take out pumpkins of any kind.
- Use whatever squash type they loved last year.
Just the one you love like a hawk - check them every morning
If this is your first year growing squash here, just ask around. Pretty much every gardener has a horror chronicle about squash bugs and will tell you what crops they lost. Use a crop that the squash bug loves to lure them in!
The Protection of Cover
Adult squash bugs locate their prey by air. You can use insect barrier netting to provide protection, draped over wire hoops and weighted down with soil around the edges. You will want to open this up when the plants begin to flower to allow pollinators in there to get all that action going that makes plant babies!!!
You can also plant your desired crop under the shade of a tree. The plants will do better with several hours of sunlight per day, but if you don’t have an insect barrier, this may be your easiest bet.
Companion Planting
Some gardeners report having luck with companion planting the squash with corn, which if planted this weekend, can grow to be tall enough to provide at least some cover. You may also try growing sorghum, or Broomcorn, around your squash. It grows very well in our area and provides a ton of shade, not to mention a host of other benefits including a lovely addition to flower arrangements, biomass for your compost pile, and a source of grain that can be ground into gluten-free flour!
Other gardeners shared that companion planting spicy peppers with the squash seemed to deter the squash bugs. Cayenne, Aurora, Jalapeños will work, and Habaneros were emphasized. Look for these at plant sales if you don't already have some started.
Direct Dealings
I can report a certain amount of luck, if not strange results, from the weekly application of diluted fertilizer. See this great article on DIY Fertilizer Tea from Seed Grower Cindy Nipper in Rigby, Idaho, on how to make a variety of ferments to bolster the health of your plants and soil.
In 2021, I worked with a version of this that was largely made from rhubarb leaves, fermented for two weeks. I had read that this was useful for deterring those dusty white aphids from kale and wound up applying it to the whole garden. It seemed to have the effect of making the squash plants inhospitable enough to the bugs that they were laying eggs on earwigs that were left on the topside of leaves, and on live roly-polys that tend to congregate around the base of the squash plants.
This season, I will be applying this deterrent to the crop I want to keep weekly, and leaving the trap crop alone outside of watering it and watching it.
Managing Squash Bugs
The population was so large last season we expect to have them this year as well. They seek shelter overnight, so you can dig a shallow trench next to your small squash plants and lay a board over it. In the early morning, you can easily knock these off into a bucket of soapy water. Check the leaves regularly. Once you see eggs, you can take a piece of duct tape to roll them off of the leaves without crushing them. Don't throw the eggs on the ground; they're tough-shelled and the nymph will hatch. You'll want to throw these away or submerge them in soapy water and then throw them away.
On your trap crop, you will want to let the population get established. Some light management wouldn’t hurt, you will want to keep an eye on that crop. Focus your full prevention efforts on your desired crop from the beginning! The trap crop plants should be removed from your garden, put in a trash bag and totally cleared out. Do this when the eggs are on the leaves, but before they hatch. You have 1-2 weeks from the point they’re laid before you’ve got nymphs.
Trellising
If you trellis your desired crop it will allow you to more easily see the underside of the leaves and manage the eggs, and pluck any squash bugs that show up.
This season we wish you the best with your squash crops.
Know that you’re not alone in the effort! Take photos and keep notes over the season. It’s a good practice for your garden, helping you increase your success each year. You are also able to trade tips with other gardeners and grow together!
