David Owens, Extension Entomologist, owensd@udel.edu
Vegetable Transplants
As we prepare to start transplants, be sure to examine them in the greenhouse for aphids and mites. Greenhouses offer perfect conditions for both – warm temperatures and protection from disease and predators. Aphids colonizing transplants will often result in leaf curling downwards as the aphids distort new growth. Spider mite feeding is fairly easy to see on transplants because plants have thin leaves. Feeding injury will appear as yellow-white stipples on the upper leaf surface. If transplants are close to being set out to harden off, natural enemies may come in and take care of aphids. The mites, however, may require treatment. Last year, I believe our heaviest mite field was the result of planting infested transplants. Mites were observed in high numbers in the field interior one week before finding mites along the edge of the field, contrary to the pattern from every other field we sampled.