Squash Vine Borer(SVB)
SVB is a common pest that attacks the most commonly grown squash by home gardeners. It is an orange and black moth that lays its eggs on squash plants.
Yes, it is a pollinator, but it is also a nuisance in the gardens. The moth emerges in the summer and lives from June to July. After appearing the moth lays eggs. The eggs laid by the moth hatch in around ten days and then begin to do damage. The larvae burrow into the stem of the squash and start to wreak havoc. Here they feed on the plant material inside of the stem blocking the water flow up the plant. After a month or so inside the host plant, the larvae exit and burrows into the dirt where it will remain until the following summer. By the time people realize it is a problem and attempt to correct it, it is too late.
Squash, pumpkins gourds, zucchini, and hubbards are highly susceptible. Despite melons and cucumbers being in the same Cucurbita family, they are not usually affected.
It is hard to prevent Squash vine borers because they overwinter, live through the winter, in a cocoon in the soil. Here are a few tips on avoiding these garden pests:
Tilling the dirt in the spring as soon as it is workable. Doing so can help bring the cocoon to the surface where a garden friend can eat it.
Applying BT insecticide spray to the plant every week. This application will help destroy the eggs and freshly hatched larvae.
Use Diatomaceous Earth. Encircle the seedling with the DE. Doing so will act as a defense but will not help if not practicing Crop rotation.
Practice Crop Rotation. Since larvae exit stem of infected plant and burrows into the dirt waiting for the following summer. Planting Squash in the same spot every year is setting yourself up for failure.
If you must plant zucchini and squash, then do so early in the season. Since the nemesis, squash vine borer is active from June-July, planting early spring ensures that the plant is done producing and removed before the summer sets. Plant a second round of squash in the middle to end of July so that by the time they reach maturity, the threat of the pest is no longer present in the garden.
Apply Row covers. Row covers are breathable, lightweight fabric that keeps pests out but allows light and sun to penetrate. This only works if you practice crop rotation. Think about it- if the pest overwinters in the soil and you plant squash in the same location the row cover will have the opposite effect. It will trap the pest inside with your squash. If you use a row cover, you will need to pollinate your squash manually.
Research different varieties. Everyone I talk to always plants the same types, yellow crookneck, straight yellow neck or green zucchini, these all belong to the same family, Cucurbita Pepo. These varieties are favorites of the SVB(Squash Vine Borer) Look into varieties of Cucurbita Moschata- Butternut, Tromboncino, Aeohaback and Seminole pumpkin, to name a few.
Yellow Traps- SVB are highly attracted to the color yellow. Try yellow sticky traps by the base of the plant. Try filling a yellow bowl with water. Moths will be drawn and hopefully drown.