What does everyone use to battle caterpillars? I u...

The main culprit are moths. They lay eggs then caterpillars. Bt sprays help kill caterpillars. Pheromone traps to lure the moths away from your plants can help. Parasitic wasps will kill the eggs. Also using the good ole pick them off by hand hopefully won't be needed. Planting dither plants,herbs and flowers which are more to their liking may lure the away from your weed.👍 help.https://www.buglogical.com/trichogramma/#targetText=Trichogramma%20are%20among%20the%20smallest,eaters%20in%20the%20larval%20stage.

Caterpillar “BT” Spray (safe biological insecticide) – This biological insecticide contains the bacillus thuringiensis (BT) bacteria which kills larva and prevents caterpillars from being able to eat. This is one of the most effective ways to kill caterpillars, and won’t hurt most beneficial insects. As a bonus, it also kills other cannabis pests like fungus gnats, worms and moths.Apply a caterpillar BT spray as soon as you see leaf damage, caterpillars or caterpillar poop. BT sprays work best on small caterpillars that are actively eating your leaves. Repeat every week for as long as you’re still seeing caterpillars, though you can give BT more often if there’s a heavy infestation. Make sure to thoroughly mist both the tops and bottoms of leaves, and apply again after a heavy rain (since that will wash the BT away). Since BT is harmless to humans, you can use BT products up to the day of harvest! One thing to keep in mind is BT spray almost instantly stops caterpillars from being able to eat, but doesn’t kill them directly. So although you may see the caterpillars alive and apparently unharmed after spraying, the BT is still doing its dirty work

I am manually removing them and manually killing them. But when I want to be preventive I am using neem oil ( it is only a repulsive )

Had the same issue. I used organic pests especially underneath the leaves but unfortunately they came back every time. The best thing is to manually remove them. Check also for eggs especially underneath leaves near lower nodes. My grandma used to put some cinnamon in a cup near the plant but I'm not so sure that'll help. Of course building a good greenhouse is a good idea for the future