I made that mistake last summer/fall with my first grow. I took the plants outside figuring probably the same as you, that the sun is awesome and how can you do better than nature with fresh air and sunshine?
I was WRONG!
What I ended up with is introducing my beautiful babies to SPIDER MITES! And then I brought my babies inside and now I have an environment where I have my plants, they have spider mites. And since they're inside now, the spider mites have no natural enemies, so they flourish like a mo fo and pretty soon, you're lovelies are all covered with them! Leaf stippling was horrible, and the webs were everywhere!
Please leave them inside where you remain in control of their health. Not only this, but you run the risk of getting busted, should someone see them and call johnny-law on you! Be safe and keep your plants safe as well!
See the attached pic showing spider mite infestation.