If you have ever grown squash, you know it can sometimes be difficult. When you plant just a few squash plants, then you will have enough for the entire neighborhood for a short time. It will be producing well and then one night will wilt down within a day. This could be the result of one of three problems that are common to squash in Tennessee. I normally will stagger my planting of squash because treating the squash plants for these three issues is difficult. Planting squash in different areas every 30-40 days will help offset your production throughout the summer.
The first hiccup with squash is the cucumber beetle that will be carrying bacterial wilt. Your plants will be producing well and then wilt overnight and die the next day. If you want to see if you have this bacterium, cut the plant from the ground and slowly pull it from the base of the plant. You will see an ooze or a slime and this is caused by a bacterium. It is often confused with squash vine borer because it will wilt the plant overnight. The main difference is the vine borer will have drilled a hole in the base of the stem.
Squash vine borers emerge from cocoons found in the ground. It is best, in the winter, to destroy any old squash debris to help slow down the population for next year. They lay their eggs in the top couple of inches of soil. Tilling your soil in the winter will expose these tender cocoons to the cold and help kill them also. Spraying or dusting the stem with approved pesticides is one option. As soon as you see a stem wilting, carefully cut out the vine borer.
Squash bugs are difficult and if you have every grown squash, you have seen one. In the summer you will see small clusters of eggs that are dark brown colored. It’s best to remove these as soon as you see them. They will suck out sap on the leaves and the fruit. The main issue is that pesticides are not effective against the adults anymore. You need to treat them when they are in the nymph stage. If you are using pesticides, use them early in the morning or late evening to not hurt your pollinating friends.
As always, if you have any questions regarding any horticulture facet, feel free to contact Lucas Holman, Horticulture UT-TSU Extension Agent, Wilson County at 615-444-9584 or Lholman1@utk.edu.