Hope you don’t mind that I googled this... one answer appealed to me...neem oil ideally cold pressed neem oil.
‘To apply, mix 1.5 Tbsp of neem oil with 1/2 teaspoon of non-toxic liquid soap per gallon of water and shake like crazy before and during application.
I find it tricky to get hold of neem oil in garden centres but in the UK the odd pharmacy / health shop has it. Hope this helps. Hope more knowledgeable people will answer.