Q. I have some pumpkin plants that are a few weeks old. They had become infested with aphids so I sprayed them with a home remedy that I found online, ( 1 part veg oil 3 parts water and a few drops mild dish soap.) Well the aphids are now gone but the plant I think is now dying. The edges of the leaves are turning brown and shriveling. I have some new sprouts in the same area and am worried for them. Is this damage due to the aphids (a virus of some sort?) or is this due to the spray or perhaps something different? Please let me know if there is anything I can do to save them or if I should just pull them to keep the rest of the garden safe. Thank you for your time.
-Mesa, Arizona
A. It is likely that the spray recipe you made is the culprit. Some soaps are pretty rough on plants. This kind of damage often shows up on leaf edges. The oil is intended to suffocate the soft-bodied aphids by blocking the breathing tubes in their skin. It also coats any eggs they may have laid. The soap is a spreader which helps disperse the oil. Sometimes spray damage is exacerbated by applying it when it is sunny and hot. It’s usually best to spray early in the morning before the sun is too strong. Based on the potion you made up I’d say you want to go with a low toxicity solution for your pests. I’d suggest you seek help at your local garden center. There are organic products specifically formulated for home garden use, many based on soap and salts. The pumpkins have been set back but before you give up on them leave them in another week and see if they push new growth.
Drew Effron
Ball Horticultural Company
www.Wave-Rave.com
