Ha - I bet you dig up your seeds to see if they've germinated
I do, so I understand why you want your garlic up. As others have said, garlic is very hardy, in fact it needs some good cold weather to do well. I have some which I planted in Dec which has shoots about 6" tall, but also some I planted just a couple of weeks ago. The first lot will grow bigger cloves, but the recent stuff will produce a crop too.
Those plastic tunnel things can be helpful for other crops, but you can make them yourself for peanuts.