Usually insect problems are self correcting in my greenhouse. bugs show up, awhile latter predators show up. I have a stash of diatomaceous earth, and I'm going to get some Green Cleaner to have on hand just in case!
I'm sure the extreme cold limits how well invasive insect species over winter up here. Plants are already well established by the time insect populations have grown enough to become a problem.
Also, for some reason unknown to me, One plant in the entire grow will attract bugs, that's where I see damage, 3 weeks to 1 and 1/2 months in. Predators must be showing up about this time also, new growth completely covers and replaces the damage, and plant begins to have a "no worries" look.