Friday, August 19, 2011

Gaining Ground in the Battle on Squash Pests - maybe.

You've all heard people talk about how prolific zucchini plants are. You've probably heard stories of gardeners sneaking zucchini onto their neighbors porch in an effort to get rid of it. But let me be the one to dispel this myth. I have had one year of prolific zucchini. Every other year, it has been a battle with the pests to keep this family in zucchini.

It isn't just zucchini either, growing squash has become war, and I fear I am on the losing side.  We are waging a chemical free war here, but I think the bugs may be smarter than I am. It was so bad last year that I swore I was not going to plant anything in the squash family this year. But then spring came and I started thinking about grilled veggies, stuffed zucchini, zucchini brownies, zucchini struedel, fresh pumpkin, and well, before I knew what I was doing hills of dirt were made and seeds were going into the ground.

The more I do this organic gardening thing, the more I am convinced the my best weapons are careful observation and quick action when pests are observed. This is the strategy I tried to implement with the squash this year. The squash have two enemies; squash bugs and vine borers.

The adult squash bugs are elusive. They are a gray color and tend to hang out in the dirt where they are well camouflaged.  I mostly see them on the actual plants in the cool of the morning. If I see them, I squish them or drop them into a jar of water with dish detergent.

Their eggs however, are more easily found. Look for copper colored eggs on the leaves. Most often they are on the underside of the leaf, but sometimes on the top. The eggs are hard to squash. I remove the leaf and the eggs and feed it to the chickens or drop it in water with dish detergent.

The newly hatched bugs have gray or greenish bodies. They almost look like a tiny spider. They are easily smashed.

While I can't claim victory over squash bugs, and can claim containment.  They are there, but by removing the eggs and destroying of the bugs that I do see, I am able to keep them from doing serious damage to the plants.

The deadly enemy to my squash are the vine borers. Adult vine borers are moths. They resemble a red wasp. I rarely see them, and if I do, I never can kill them. They are too fast. They lay tiny black eggs on the stems of the plant. I've looked for the eggs. I've removed a few things that may have been eggs, but then again maybe they were just dirt.

I don't know I have a vine borer until I see something like the picture to the right. See the yellow stuff that looks like chewed fibers. Yep, that is the evidence of a vine borer. Or if it is dry it will look something like sawdust.

When the stem is cut open, you'll find a white grub like worm with a black head. The one pictured on the left is a pretty big one. The tiny ones can be hard to see.

The only thing I know to do when these bugs are found is to split open the stem and destroy the bugs. This works pretty well if the borer is only in a leaf stem. When they are in the main stem of the plant, you can split it and mend the stem by covering it with dirt or wrapping it up, but the plant is severely weakened.

The first time I found borers this year, I split the stems, destroyed the borers, and covered the stems with dirt. The plants came through this nicely. They stayed upright and green. They looked healthy, but fruit production came to an abrupt halt. I wasn't able to keep up the borer vigil, and the next time I checked over the zucchini they were so infested with borers that I pulled all but one plant. It is so frustrating. My next step is to replant, and try again. 

Another thing I noticed this year is the pumpkins are coming through these attacks better than the zucchini or summer squash. I have not been able to keep as close of a watch on the pumpkins, and vine borers are there. The pumpkin vines put down roots that seem to take up the slack where the borers have attacked. Maybe I should try a vining variety of zucchini?

The war is on, and though I think I gained a little ground this year, the bugs definitely have the advantage. Any one have a secret weapon they'd like to share?


  1. Are these pests drawn to light?

  2. Steph, we have sworn the same about squash here! Other folks say their squash are taking over. I think I harvested one or two zucchini and maybe the same of yellow squash (I will be brave and tell you that was from FIFTY plants!) Yeesh! From what I hear, winter squash are less susceptible to the vine borer. I would think the vining squash would be less susceptible as well. I hope, anyway. :)

  3. Try keeping a row cover over your squash plants until they start flowering. Be ready to do succession planting and expect that the plants started later in the Summer will do better. Vining varieties of squash always do better because they put down roots at other places along the vine. Then when the vine borer strikes at the main stem, there are other rooted areas of the plant to keep it alive. (Upright squash varieties are more vulnerable.) You can encourage this by piling dirt in different places along the vines. Lastly, interplant aromatic flowers / herbs (Borage, Basil, Cosmos, Zinnea, Dill, etc.) along with the squash plants. They attract beneficial insects (who will eat the bad guys) and pollinators, look pretty, and confuse the nasty critters a bit. Good luck!

  4. Mike, They aren't drawn to light that I've noticed.
    Becca, :(
    Anonymous, I did have marigold and basil close to them. One year I had radish too. I have thought about row covers, but don't the squash bugs winter over in the ground? I was afraid that row covers would just give them a nice little safe habitat. Any recommendations for vining varieties of summer squash?

  5. We've had worse years than others and the best thing to do besides hand picking is to use the vacuum cleaner. Yes, you read right. We just lugged the Hoover bagless right out to the garden and sucked up all those little creepy bugs and sucked the eggs right off the leaves and enjoyed the zucchini the rest of the season. Give it a try.

  6. oh that is funny, but effective I am sure!

  7. Some squash bugs will sneak under a row cover but absolutely no vine borers will get at the plants until you uncover them. I've not been able to find vining varieties of summer squashes. :( On the winter squash front, I'm told that butternut is especially resistant but I'm not sure if I've seen that in action. This year I was sick and did not weed out a lot of "volunteers" (lemon basil and tomatillos mostly), and I think that made a difference. I've had the least damage to my squash plants this year of all others.

  8. I've had some success using a large sailor's needle to pierce the bugs in the stem, rather than splitting it open. If I have to make multiple stabs I try to keep them all in line so as to minimize the amount of damage to the plant. This works best when I'm pretty sure I know how far and which way the critter crawled.

  9. I have had the exact same bugs on my zucchini this year. They have been horrible. And I didn't have any luck getting rid of them. Thank you for this post and I am going to keep investigating ways to prevent them before they become a problem. We garden chemical free also and it has been a struggle to keep my husband from wanting to just spray something to get rid of them.

  10. Stephanie, Lisa Minney from Two Lane Livin' said she had great success by mixing 1/2 cheap cooking oil and 1/2 water in a spray bottle and spraying it on her plants. She had the little rascals real bad. I didn't garden this year, but plan to keep a bottle on hand for next year. Hope it helps.

  11. We are having the same problem too. I hate handpicking them off so I have been using a shop vac and then opening it in the chicken yard with the chickens all around. Seems to be working although you have to keep finding the borers. Good luck!

  12. We call the bugs "stink bugs" and although they do not give off a significant odor, they definitely "stink." Best to you!