I've been growing all kinds of garlic for many years, and all I ever use is fall leaves which stops the freeze/thaw cycle from heaving the bulbs out of the soil.

I typically get bulbs that are much larger than the ones you can buy in the store.

After the leaves have fallen, I do the last mowing with a bagger and pick up a great mixture of half-shredded leaves and grass clippings. Our chickens range in the garden in winter, so I then cover the mulched bed with an arch of wire fencing. These early turbans are liking it.

OK, you two have convinced me its going to be a long time before I Buy any mulch for my garlic...
I was gonna ask how thick I should apply , but since y'all have provided such great pictures...thank you!!!