Note to readers, attached is the complete final report for FNE98-203
Squash vine borer has been a persistent problem for Mr. O’Hara, who grows vegetables organically in eastern Connecticut. His SARE project involved using cotton row covers and varying the planting dates of his squash, as deterrents for this pest. The row covers present a physical barrier to the borers, but must be removed at flowering to permit pollination. In varying the planting dates Mr. O’Hara hoped that the very early plantings might already be bearing fruit by the time the first squash vine borer moths arrive around the first of July, and that they would have departed by the time the row covers were removed from the late plantings.
Mr. O’Hara planted squash at intervals from May 6 to July 15. The earliest planting was started indoors and later transplanted to the field. Half of each planting was covered with a cotton row cover, held over the plants on wire hoops, and half was left uncovered.
Results: The earliest plantings yielded the best. The first two plantings (5/6 and 5/25) were already yielding before squash vine borers became a problem, and being larger and hardier than the later plantings, were better able to resist the infestation when it arrived. Later plantings suffered even if they were covered, because the covers had to be removed when the plants flowered in the middle of the infestation.
Squash plants growing under row covers grew faster and appeared healthier than uncovered plants of the same planting date. Besides keeping squash vine borers off the plants, the row covers kept striped cucumber beetles and squash bugs away, early in the season, and also deterred deer and groundhogs. The greatest yield, by a considerable margin, came from the covered plants of the earliest planting.
Mr. O’Hara recommends the row covers. Besides deterring pests, they are easy to handle, can be used over many seasons, when worn out they can be composted, and, at 30¢/foot, they are economical. He also recommends early planting, but intends to continue to experiment with very late plantings for winter squash.