| My local nursery reviewed a suspect leaf and announced that I have spider mites on my rose bushes, which will strip the leaves from the plant and they said there are no really effective sprays for this insect. May I have your response telling me how to address this problem. Thanks, Wayne Graybill |
| Wayne, I apologize for this delayed reply to your gardening question and hope it is still helpful to you. You might first have your County Extension Office also examine a few affected leaves since spider mites cause loss of color in tiny specks but don't "strip" the leaves off. Take some leaves in a plastic bag so any pests present don't escape on the way. Strong sprays of water from beneath the plant will dislodge the pests and significantly reduce their ability to build up to damaging numbers. Use a high pressure, fine droplet spray once a week, making sure to contact the undersides of all the leaves for best results. The safest products to use are insecticidal soaps and horticultural or summer (not dormant) oils. Make sure and spray upward from beneath the plant as these products only work when they contact the pests. Spray early in the day when temperatures are cool and do not mix the spray stronger than the labeled rate. Retreatment every 10 to 14 days may be needed. Avoid oil sprays when temperatures rise into the upper 80's and above. Thanks for the question. Best wishes for a wonderful gardening season. Please stop in again soon! |
