Common Rose Pests Identifying Problems
Summer is here and judging from my mail, many gardeners have roses that are showing symptoms if insect infestations.
Common Rose ProblemsHoles in Leaves and Flowers
And What Causes It
Shiny blue-green beetles, Japanese beetles
, are the most common culprits. How to control them: Pick off beetles in early morning and drown them in water. Use pheromone traps. Apply milky spores disease, or a product made specifically for grub control to kill lawn grubs, which are Japanese beetle larvae. Spray plants with rotenone.Speckled, Pale Foilage
This is caused most likely by Spider Mites
. Tiny insects form fine web on the plant and sucking its juices. They are worst in hot dry weather. How to control them: Keep plants well watered. Spray the undersides of all leaves with a blast from your garden hose. To avoid this next season, spray in very early spring with dormant oil. That will smother any overwintering spider mite eggs. Choose a spray that specifies control of spider mites on the rose plant you want to spray.Streaks and Spots on Flowers and Young Leaves
Tiny, darting yellow-brown insects called Thrips
cause streaks and deformed buds that fail to open, and on flowers. Most common on pale-colored roses. To be sure it's thrips, you should collect a damged flower and shake over a white paper. Thrips will appear as tiny yellow brown flecks moving across the paper. How to cotrol: Apply insecticidal soap or pyrethin, or spray with product specifying Thrip Control. Prune off and destroy thrip-infested flowers and buds.Leaves Eaten Between the Veins
, green slug-like worms, up to 3/4 inch long with brown heads may be found feeding on the undersides of leaves. The lacy, translucent layer of tissue that remains will turn brown. How to control: If there is little damage and you can spot the slugs, simply pick them off by habd and dispose. I usually drown them. For more severe infestations spray with an insecticide containing acephate or carbaryl.
If your roses show any of these symptoms, use this as a guide for indentifying and controlling common rose pests.
PS: Let me know if you have been helped by identifying any of these rose pests in your garden.