Is there a insect "repellant" for vegetable plants and even small trees?

We're having a horrible insect/pest problem this year, here in S Texas, because we didn't get any freezes last winter and we had an incredibly wet spring. I'm looking for a product that will keep more bugs (even grasshoppers) from moving in once I've sprayed with an insecticide, like Neem. I saw some garlic based liquid somewhere but now I can't find anything online. I'm hoping for something I can order from Amazon because we live a LONG way from a gardening store.

Any advice would sure be appreciated!!