Growing Great Garlic in Northern California
by Sara McCamant, Community Seed Exchange
When to plant: The best time to plant is from mid-October to mid-November. Some people push it til late November but I find there are more problems with rotting cloves the later I plant. Spring planting produces smaller bulbs but does work.
How much to plant: Each clove produces one head of garlic; think about how many heads of garlic you can use in 10 months. A head of garlic varies greatly in how many cloves there are, depending on what type of garlic it is. The clove size also determines the size of the head: small cloves produce small heads, large cloves produce large heads.
Varieties: There are two important designations of garlic:
Hardneck produces a seed stalk, normally is easier to peel, and has larger cloves with fewer small cloves. It has a stiff neck and cannot be easily braided. It does not store as long and should be used first. Usual store time is 4 to 5 months.
Softneck does not produce a seed stalk. It usually has layers of cloves so can have more small cloves. It can be braided and lasts much longer, 8 to 10 months typically.
Soil preparation: Garlic likes fairly rich, well-drained soil. (Because it grows in the winter it will rot if soil is too wet. Heavy clay soils are the most problematic for garlic.) It is recommended to amend with compost and some balanced fertilizer before planting.
How to plant: Break up a head of garlic; leave the skin on. The larger cloves produce larger heads. I plant only the large cloves for my main garlic and small cloves for spring green garlic. Lately there have been problems with garlic rust, so plant the garlic farther apart for more air circulation and to minimize the plants touching each other. I now recommend that cloves be planted 7-8 inches apart in all directions (I used to say 5-6 inches apart). Plant with the pointy side up and the root side down, about an inch and a half deep. Label them with the variety name and date planted.
Pests: Gophers love garlic, so it will need protection — grow either in a raised bed or in gopher-wire cages. There are not that many other pests of garlic in California. Slugs can affect leaves in the spring. Garlic is also susceptible to mites and nematodes, though I have never seen those.
Green garlic: You can harvest the immature heads of garlic while they are green and use them as you might a leek or green onion but garlic-flavored. Plant the small cloves for a green garlic harvest in their own spot.
Rust (Puccinia allii) has become a huge problem in California. Late winter you may notice some orange spots appearing on the leaves; that is the beginning of rust. Carefully pick off the leaves and throw away. It can severely reduce the size of the head but seldom kills the whole thing. Best practices are to rotate where you plant any alliums (onions, leeks and garlic) — a four-year rotation is good. Also plant in the sunniest location to lower the amount of moisture on the leaves. Less nitrogen also may help reduce the likelihood of rust.
White Rot, Garlic Mosaic and Downy Mildew are other possible diseases that are similar to rust. Best to rotate where you plant it, keep good air circulation, and plant in well-drained soil.
Care while growing:
Weed. Garlic hates being crowded by weeds; it is important to keep the bed well weeded.
Mulch. After the garlic emerges from the ground, mulch with a couple of inches of straw to prevent weeds from growing.
Fertilize. Mid-January to mid-March, fertilize monthly with fish emulsion and a seaweed fertilizer. Do not fertilize the last month before harvest.
Water. Since it is growing in the winter, it needs little extra watering. If we have a dry winter it is good to think about some watering in spring. Because of rust issues, drip irrigation is much preferred.
Flowers. Hardnecks send up a flower stalk, and that should be broken off to keep the energy in the bulb. The scapes (flower stalk) are a tasty treat to be sautéed and eaten.
Harvesting: Stop watering a few weeks before harvesting. It is best to harvest garlic when half of the lower leaves are yellow or brown. Some of the hardnecks will crack open if left in the ground too late. It is important not to leave garlic out in the direct sun once you have harvested, as that can cook the head. Brush off the dirt as best as possible.
Curing: Let the garlic, with the stalk and roots on, cure out of the sun in a warm, dry place — hanging in a barn or spread out on pallets in the shade — for about 2-3 weeks. Then clean off all the dirt, brushing off the dirt and peeling dirty outer skins, and trim the roots before storage. Try to keep as many skins on as possible.
Storing: Garlic stores best in cool and dry conditions. Keep it below 70 degrees but above 40. If you want to get technical, the ideal storage condition is between 55°F and 65°F, around 60% humidity, with good air circulation. Garlic tends to sprout at colder temps (thus, no refrigerators!) and dry out in warmer temps. Light is not a factor in storage, as long as you keep your garlic away from direct sun.