Odorless liquid extracts and powders or tablets are also sold, but the effectiveness of some of these products has been questioned. Medicinal value of commercial garlic preparations is highly dependent on the content of allicin and its transformation products, which are in turn highly dependable on the method of preparation. This procedure is known as cracking, and is labor-intensive if done by hand. Buyers should purchase the healthiest stock available. Only healthy cloves should be planted, and it is preferable to plant the largest cloves available.
Growers generally retain a part of each crop for replanting the following season.
Approximately 700-1000 kg will plant 1 ha. There are hundreds of cultivars of garlic available worldwide, but only a small number have been tested in Saskatchewan. Yields have not always been consistent within a given cultivar. It is recommended that growers do their own cultivar trials prior to undertaking commercial-scale plantings. Local growers may be able to provide or recommend other cultivars.