Question: For the past couple of years, my astilbe plants have come up okay but after the flower shoots come up something seems to eat them. I did notice that one of them had almost like a spider web in the middle of the plant. I have two astilbe plants and they are about 15 feet apart yet this happens to both of them. Any suggestions would be greatly appreciated.
Answer: You might want to get up close and personal with your astillbe plants to see if you can find any insects residing within. Generally spiders catch insects, so if there's evidence of a plump spider there, then he's eating something of importance. About the only insect that has a fondness for astillbe is the Japanese Beetle. These beetles like raspberries, roses and most fruit trees, but they have a preference for at least 275 different plants, one of which is astillbe. The adults are a shiny coppery color with a blue-green head. The grubs are gray-white with a brown head. The grubs pupate in the early summer and emerge from the soil as adults, ready to consume plant material from summer through fall. Start watching your astillbes for damage and see if you can catch the culprit in action. You can hand pick the adult beetles and remove them from the garden. In the fall, cultivate the soil to expose the grubs. Cultivate again in the spring to expose any that are left.
Q&A Library Searching Tips: