[coriolis]

I currently have a high tunnel, but all my life, I’ve done flat earth gardening, both in and out of a high tunnel. IMHO, the biggest advantage of a high tunnel, is that the plant leaves do not get wet, thus many of the diseases that are common to outside plants are either not as severe or non-existent in the high tunnel. Obviously, I have screens on the side of the HT which prevent many of the pests from entering, but for me, the lack of wet leaves gives me the ability to harvest my my crops for a much longer growing season. For example,I harvest my tomatoes till late October up here in Connecticut.