Will plants grow below 30% Rhumidity ?

As the title says.
My friends plants are 2 inches tall - 3 weeks old !!! The humidity is realy low, but i didnt think this would cause a problem , provided the plants receive enough water to their roots?

yes, plants will grow just fine below 30% RH. If i had to take a guess as to why your friends plant isn't growing, i'd say he's most likely overwatering it? Too much water and/or keeping the soil constantly wet without letting it dry out will result in very slow growth.

yea, they will grow, in fact the lower the humidity the less chance you are to get spidermites! but that doesn't mean aim for a lower humidity. Well 2 inches sounds pretty small, sounds like stunting to me, what kind of lighting / soil / process did he/she go through when they started.

Thanks guys.
Im guessing its over watering that is the problem. But as far as i was aware , coco is impossible to over water ?

800w , 12/12 from seed ( they are autoflowers ) 75 day 60 night temp