For some reason my plants won't grow anymore in my main hood. I can still plant them, water them and they sprout weeds, but they don't grow anymore. This only started happening a few days ago, so I tried taking out my downloads and testing it in another hood. Everything went fine there even when I put all my downloads back in, but the problem persists in my main hood

That tells you it's one of your downloads. Try running the hack detection program from sim wardrobe.

Even if the plants grow fine with all my downloads in another hood?
I tried the program too, it doesn't show anything

Try and delete your cache files and then if they still wont grow then replace them and see what happens.

I think it was the way I built the greenhouse that was causing trouble, because I could see the plants were growing if they placed them outside. I rebuild them with glass walls on all sides and it works now. It makes no sense to me, but it fixed the problem.
Thank you for your help

Sorry I didn't see where you said they also grew fine with the downloads in. Glad you got it fixed.