To my understanding, garlic can take the cold, freeze, snow and what not. So I don't see a need for growing it under hoop. Unless, maybe, the purpose is to accelerate its bulbing and maturity.

Yes, the best use of a protected winter growing space in your climate would be growing less-hardy turbans or other early-maturing strains, or growing garlic-scallions ("gallions") to eat during the winter months. Great use for stored garlic that wants to sprout.

Don't some varieties of garlic prefer full winter conditions?

Creoles, artichokes and silverskins all do well in a warmer climate so ought to be good in your tunnel house.

Here is a link that might be useful: garlic varieties

elephant garlic from Niagara Falls.

In early Jan., I installed a low tunnel on a garlic bed that's my earliest variety- siskiyou purple. We'll see what happens. :)

Seedeater I'm thinking about doing this, what happened?