Spider Mite Problems In Roses
Rose leaves stippled and dirty? Could be spider mites. Learn what they are, how they manifest, and what you can do about damage and infestation.
What is it?
The mites, related to spiders are a major pest to many rose gardens and greenhouse plants. They cause damage through their sucking action, which removes sap from the undersides of the leaves causing the green leaf pigment to disappear gradually.
What does it look like?
Roses will develop bronze colored leaves that look stippled and dirty. The undersides of the leaves or new growth may have a silken webbing adhered to them. As a result of the mites feeding, the pigment is drained from the leaves and they gradually lighten as chlorophyll disappears. Often the leaves will drop off.
How does it manifest?
Mites are active throughout the growing season, and the more motes you have, the more damage your roses may endure. Severely infested plants produce few flowers and become increasing lighter and more stippled looking as the leaves brown and are sucked dry of sap. Most mites favor weather above 70°F with a dry climate. By midsummer the mites multiply to tremendous numbers if not treated.
What can you do about it?
When you notice the first signs of spider mite damage, cover the undersides of the leaves thoroughly with a miticide which contains hexakis. This treatment should be repeated twice more at intervals of 7 to 10 days. Also repeat the procedure if a new mite infestation occurs.