what nutrient/bug problem is this?

[Kuba]

hey all so recently i've been seeing these small brownish spots on my plants. it seems to only affect the top and it started to spread to other nearby plants, this makes me think it's some kind of bug but idk for sure. any help is much appreciated

 

[mysticepipedon]

Is that outdoors?

 

[Kuba]

Is that outdoors?

yes, outdoors. still dont know what it could be

 

[Ponky]

Caterpillars and inch worms. 85% certain. Threat low to medium.
Garden Safe® Brand Bt Worm & Caterpillar Killer. Is a low toxicity product.