One very natural trick for general gardening purposes (i.e. deterring bugs of various species from diverse types of plants) taught to me by someone I once knew was to simmer a few hundred grams of very hot dried chilli in water for about 30 minutes, then strain it, and put it in an empty spray bottle, and spray those bugs. Capsaicin is one of nature's bug-repellants, and though I'm sure there are some insect species that can handle it, most won't appreciate it very much and will piss off. Be sparing, though, and maybe hold off for a few weeks before harvest: Your plants will absorb some of the capsaicin through their roots, and your produce will have a "spicy" flavour if you use too much or too close to harvest.
Also, I just remembered that you'd better have some good ventilation, somewhere away from the kitchen to put any pets, housemates, yourself, etc. when you're boiling up that chilli water! Otherwise, you're basically capsicum-spraying the entire interior of your abode and you and anyone else in there will have some unpleasant coughing fits, eye pain, etc. And be careful with the juice (e.g. don't tough your eyes or other sensitive bits

after handling it and before stringently washing your hands)! Capsaicin ain't nuttin' to fuck with.