Posted: 08/03/2015 at 15:34
Have a look at this link for some info.
I make up a spray of neem oil and as soon as growth starts in April I drench the foliage. Any spare solution goes onto the soil below the plant as the earthworms are supposed to love it. I repeat spray every couple of weeks.
Neem is best used prevantatively. It is totally organic and although it stinks a bit is easy to mix up and apply.
I got mine off ebay .... wasn't expensive for a big bottle which will last ages. At room temperature it is solid, but goes liquid again with a couple of hours in the airing cupboard.
I spray my lilies (and fritillaries), a couple of gooseberry bushes, and my solomon's seal as it works for sawfly.
Works for me.