What can I do to get rid of rosemary beetles?
PIPPA SAYS They can be a real menace! It is worth remembering that as well as rosemary and lavender, these beetles and their larvae will also damage sage and other closely related plants, so check those, too. On the whole, the beetle rarely does enough damage to have a significant impact on the plants’ health and so I wonder if there may have been some other problem affecting your rosemary?
Try to collect as many beetles as possible by hand – you can speed things up by spreading an old sheet beneath the infested plants and then shaking them. This way, you can collect significant quantities of these pests. There are a number of natural predators of the rosemary beetle including ground beetles (which eat the larvae), frogs and toads, so ensuring that your garden is a good place for these creatures to live will also mean that you have plenty of help.