I read your tips about leaf miners (I have them here in Sweden where the pest variety affects Masterwort especially and doesn't seem to have natural enemies). You recommend a special pesticide which can be used anytime and absorbs into the leaves, killing the eggs and/or larvae. Which pesticide and where may I order it?
Certified GKH Gardening Expert
Neem oil is very effective for leaf miners. A search online will bring up many places that sell it. It may also be at your local garden center sold as neem oil, leaf shine or fruit tree spray. You can check the labels to make sure that the product you are buying cointains neem oil.