Wrath of the squash borers: Fall of the Cucurbita

Garden journal July 2019: High summer in the Southeastern United States

harvest on July 1st

I have waged a rearguard battle against my annual scourge, the squash borer, season upon season. In our first skirmishes, I went on the offensive, driving them out with blade and sprayer. But this proved to be ineffective, with the demon worms rising again and again to suck the life out of my zucchini, pumpkins, and watermelons. Today, we have an uneasy truce. This is my story.

Lifecycle of the borer

The squash vine borer female lays eggs on the underside of leaves or stalks. Caterpillar larvae emerge and chew into the vines of members of the Curcubita genus. These are not cute caterpillars from the children’s story but look more like a sightless, pallid worm of death. I put a photo originally in here but was concerned it would give nightmares to the squemish.

Photo credit

An infestation can be determined by wilting of the leaves despite adequate watering and the appearance of fine sawdust on the stems of the plant (called frass). Plants begin to have poor yields and then die due to a lack of water and nutrients reaching the leaves.

Prevention is the best medicine

To control the borer, the best method is to manually remove the small eggs on the underside of leaves before hatching. You can also wrap the base of the stem with fabric (I save socks with holes for this). I have sprayed organic pesticide very conservatively around the time of the broods but I am really reluctant to do this since all the squash are flowering and this could endanger pollinators.

Once infested, options are limited. Some people report successfully cutting the vine with a razor and manually removing the grub. I have tried this to no avail. Instead, I sow seeds very early (just after last frost). When combined with regular watering using a drip irrigation system, I can have 4-6 weeks of harvest before yields drop off due to infestation. I have read that commercial growers do not have significant problems with the borer so I put in a lot of plants during one season. I also only plant the most vulnerable varieties (e.g., zucchini) every other year. As always, I rotate planting space too but I am not sure this is exactly effective for the borer.

my zucchini this week, note the small slit on the stem where the larvae burrowed in

July on the homestead

We are in the last week of zucchini harvest. I will pull the plants and burn them this weekend as they will not produce much more due to infestation. We are harvesting more tomatoes than we can eat but not enough to can right now so we will freeze bags of cherry tomatoes for omelettes for the next year.

These tomatoes (Matt's Wild) are prolific but very laborious to pick. I grow them every year to mostly give away to friends, family, and business associates

Thank you to everyone who supports the Steemit Community Garden Challenge. This is my first month on Steem so I am honored to have this as my first entry.