I noticed about 2 weeks ago my Pumpkins vines were drooping and dieing. I...

Asked August 28, 2013, 3:38 PM EDT

I noticed about 2 weeks ago my Pumpkins vines were drooping and dieing. I looked at the base and found white grub worms eating the base of the plant, I removed as many as I could find but i am sure to no avail. For next year how do I prevent I believe they are called the Squash Borer's? Please help as I have 5 grand children that need grandpa to produce. Thanks Jim

Scott County Minnesota

1 Response

You may be experiencing the Squash Vine Borer. Once it bores into the bottom stem of the vine, insecticides will not kill it. Identification Squash vine borers are small, fat, white caterpillars about 1 inch long; they are the larval form of a large moth that is black and orange with clear wings. These worms will attack primarily squash and pumpkins and occasionally cucumber and melon vines. The adult female moth lays eggs on the vines in June and July. The larva will then emerge and bore tunnels in the plant's stems to feed for 4 to 6 weeks while disrupting the flow of water and nutrients in the plant. Yellowish-green excrement or insect frass is very evident around the holes created by the borers. Most severely damaged plants will wilt and collapse and eventually die. Prevention and Control There are a few ways to prevent squash vine borers. Floating row covers are really the only way to prevent the moth from laying eggs on the vines. But be sure to remove the covers when the flowers bloom to allow pollination by insects. Crop rotation and early planting might help too, since these borers overwinter in the garden soil and debris. Once the plants get up in size, dust or spray the vines with an insecticide such as Malathion or Sevin every 7 to 10 days. Unfortunately, insecticides will not work once the borer has tunneled into the plant. Slitting the damaged vine near the holes and frass and then removing and killing the borer might help save the plant.