Cornell University recommends purchasing garlic bulbs from mail-order suppliers or a local garden store. The site suggests local stores are the best since they stock bulbs suitable for the local climate.
Specialist catalogs offer a wide variety of garlic types that local stores may not carry, notes Good Housekeeping. Garlic can be grown from supermarket bulbs, but Cornell University suggests that is not a good idea as they can be carriers of diseases and may not be suited the climate. Also, grocery store bulbs may not sprout because they are often sprayed to discourage sprouting once they have reached the store.