The best crops of garlic are planted in the fall and harvested in midsummer the following year. Garlic survives bitterly cold winter underground, grows quickly when the weather warms in the spring and makes bulbs in the summer. In northern areas, plant cloves 4 to 6 weeks before the ground freezes. This gives the plant time to develop roots, but not enough time to make leaf growth. Where winters are milder, garlic can be planted from October through January.
Garlic needs fertile, loose, well-drained soil with lots of organic matter and a pH between 6 and 7. When you receive your garlic bulbs (also referred to as 'heads'), carefully break them apart into individual cloves. Sow separated cloves with the root or blunt end down. Where winters are mild, plant cloves 1 inch deep. In cold areas, plant them 2 to 4 inches deep. Space the cloves 4 to 8 inches apart. (The exception is Elephant Garlic which is sent as large, individual cloves which should be planted 4 to 6 inches deep and spaced 8 to 10 inches apart). Mulch the garlic rows lightly immediately after planting. Garlic has no problem growing through an inch of mulch in spring. In cold areas, mulching with an additional 4 to 6 inches of marsh hay or straw will keep the soil warmer so the root growth can continue longer.
In spring, when garlic sprouts appear, remove the mulch. It can be pushed alongside the plants if you wish and used as a side mulch. Fertilize moderately with a high nitrogen fertilizer. Garlic also likes being sprayed with a high nitrogen fertilizer every 10 days to two weeks. Once bulbs begin to form, discontinue fertilizing to get the best quality bulbs. Keep the soil moist during the growing period, but water less frequently as harvest approaches to avoid molding and staining, plus the bulbs will store better.
When there are still 4 to 6 green leaves remaining on the plant, check the bulbs to see if they are ready to harvest. Each leaf represents a layer of skin on the bulb, so if there are no green leaves when you harvest, the result may be exposed cloves with no skin layers covering them. Loosen soil with a fork to remove bulbs, brush off the soil and move them out of direct sunlight. They may be either tied in small bundles and hung up to dry in a cool, shaded, well-ventilated location or spread out in single layers on screens or slatted shelves. After curing for 2 to 3 weeks, hang the dried bunches in a cool, shaded location. You may also cut the stalks off 1/2 inch above the bulb and store them in mesh sacks with good air circulation on all sides. Perfect storage conditions are 45 to 55 degrees F. at 50% relative humidity. Storage below 40 degrees F. actually makes garlic sprout.