You will definitely have to harden off tender GH grown plants. It will help them if you have a fan blowing on them while they're still in the GH so stems will be more sturdy and resilient. But filtered sunlight inside and full sun on the outside are completely different. Cheryl

I had no problems last spring with my tomatoes going direct from my GH to the garden. Most were about 12 inches tall or taller. The GH has a large swamp cooler blowing air when ever it got up to or over 85 degrees. High altitude Colorado bright sun. It could depend on the quality of the GH material.
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