Updated: Aug 3
Garlic is a species of bulbous flowering plant in the genus Allium. Its close relatives include the onion, shallot, leek, chive, Welsh onion and Chinese onion. The botanical name of garlic is Allium sativum. It is native to Central Asia and northeastern Iran and has long been used as a seasoning worldwide, with a history of several thousand years of human consumption and use. It was known to ancient Egyptians and has been used as both a food flavoring and a traditional medicine. China produces 76% of the world's supply of garlic.
The plant may produce pink to purple flowers from July to September in the Northern Hemisphere. The bulb is odoriferous and contains outer layers of thin sheathing leaves surrounding an inner sheath that encloses the clove. Often the bulb contains 10 to 20 cloves that are asymmetric in shape, except for those closest to the center. It produces hermaphrodite flowers. It is pollinated by bees, butterflies, moths, and other insects.
Table of Contents
1 - 3 feet
2 - 12 inches
between 6.0 - 7.0
Growth Nutrition of Garlic
Garlic has a moderate to high demand for nitrogen, so fertilizer can be incorporated before planting. Apply phosphorus and potassium according to soil test results and incorporate both before planting. Planting in October will help get roots established before the ground freezes.
Potassium (K) is a vital nutrient for increasing garlic yields. Proper application rates and timing are critical for generating a yield or quality response. As crop yield increase, the amount of K required also increases, along with all other nutrients.
Types of Garlic
The many sub-varieties of garlic fall into two basic categories: hardneck and softneck. Softneck varieties are best grown in warm climates, while hardneck is the garlic of choice for northern growers. Softneck garlic stores and travels better than hardneck garlic, and it has a stronger flavor and generally produces larger cloves. If you want a milder garlic taste, try elephant garlic—it's actually more closely related to leeks than it is to true garlic.
Hardneck garlic is so named for its stiff central stalk, or neck. It typically produces fewer cloves compared to softneck bulbs. The cloves tend to be all one size, forming a circle around the plant's neck. Popular varieties include:
Rocambole: Has very thin skin that peels easily, but bulbs don't store as long as other types. Also called serpent garlic, due to its curling scapes, this is one of the most widely grown varieties.
Purple striped garlic: Includes several striped varieties with flavors ranging from mild to pungent; Starbright is prized for its nutty flavor and storage quality, and Chesnok is good for roasting.
Porcelain garlic: Bulbs have only a few large cloves and thick skin that helps them store well. Georgian crystal is a mild variety, and Romanian red is spicy hot and tangy.
Often thought of as “true” garlic, softnecks account for most of what you’ll find at the supermarket. This is because they are more productive, easier to grow – especially in warm climates, and they store for longer. They’re called softnecks because their above-ground stalks will flop over in the summer, a sign that they are ready to harvest.
Artichoke: Commonly grown commercially. It is identifiable by its two concentric rows of cloves (and its resistance to peeling). Red Toch has cloves striped with red and pink and a balanced flavor.
Silverskin: Named for its silvery-white skin, the bulbs have numerous small cloves and a sturdy neck that is good for braiding. Most types have a stronger flavor than artichoke types. Two bold and full-flavored varieties are Nootka Rose and Rose du Var.
While not a true garlic, the enormous Great-headed (Elephant) garlic behaves like a hardneck type. Despite its size, it has quite a mild flavor. Most types are about 90 days to harvest, once growth starts.
Great-headed (Elephant) garlic is not recommended if you’re looking for a garlic taste. It’s less hardy, and more closely related to leeks than other varieties. The flavor is more like onion than traditional garlic. Bulbs and cloves are large, with about 4 cloves to a bulb.
Some of the types of garlic varieties are:
Chesnok Red (Allium sativum): Chesnok Red is an attractive hardneck purple stripe garlic that originates in the Republic of Georgia. It is very cold-hardy. It has wonderful robust flavor, a large number of cloves, and a long shelf life. The outer skins are white but peeling reveals the lovely red tones.
Bogatyr (Allium sativum): The cultivar name means "penicillin" in Russian and refers to this garlic's rich supply of magnesium, vitamin C and vitamin B6. The flavor is rather intense; this hardneck purple stripe garlic is a good one for pickling or fermenting, in addition to imparting spicy flavors in cooking. It has a good shelf life.
Music (Allium sativum): A popular hardneck porcelain variety at local farmers' markets, this one is perfect for if you only want to grow one variety. The white bulbs usually contain between 4 to 5 large cloves. It has a rich and musky flavor, rather "hot" when raw, and a hardy garlic that has excellent longevity in storage. This garlic is believed to have been brought to Canada from Italy and named for Al Music, a tobacco farmer who became a garlic grower.
Nootka Rose (Allium sativum): This is a popular silverskin softneck garlic that is a good choice if you want garlic to plant in spring. The bulbs produce around 12 to 20 cloves apiece, and the flavor is rich and strong. It is a Northwest heirloom that originates on the San Juan Islands off the coast of Washington State. It is suitable for growing in warmer zones.
Creole Red (Allium sativum var sativum): Once considered a type of softneck garlic and subgroup of the silverskins, there is now agreement in the horticulture world that Creole garlics are their own unique variety. Under certain conditions they may produce a central stalk, behaving more like a hardneck. Widely grown in California and Texas, they prefer warmer temperatures but can be grown in colder climates, though the bulbs may be smaller. Their colorful magenta clove skins and compact shape give this garlic a unique look, and their deep flavors are suitable to a wide range of uses. One of the most commonly grown cultivars is 'Creole Red' (pictured); other favorites include 'Ajo Rojo' and 'Ajo Morado'.
Rose de Lautrec (Allium sativum var. sativum): Also called "French pink garlic," this aromatic Creole garlic originates in the south of France. It is growing more popular with garlic lovers for its beautiful color and excellent, subtle and slightly sweet flavor. You might have to do some searching to find it available for purchase, but some nurseries that specialize in heirloom and speciality garlic varieties will probably have it.
Spanish Roja (Allium sativum var. ophioscorodon): This classic hardneck rocambole garlic is considered a must-have in the garden for cooks. It is sometimes referred to as 'Greek Blue', attesting to its rich history. It was brought to Portland, Oregon from Europe in the late 1800s and is believed to have originated in Spain. This garlic has a pungent and complex flavor that is fairly hot when raw, more mellow and slightly sweeter when cooked. The paper outer skins are white but peeling reveals reddish purple or tan coverings on the cloves. It grows well in colder zones.
Korean Red (Allium sativum): This sturdy hardneck porcelain garlic is getting more popular. It produces an abundance of cloves whose skins have an auburn to red color. It's said to have a citrusy flavor and is excellent for roasting which imparts a sweet complex flavor. It matures fairly early compared to other hardnecks and has a somewhat conical shape. It's adaptable to many climates.
Russian Giant (Allium sativum): Russian Giant is an attractive marbled purple stripe garlic with reddish purple clove wrappers. It has nice fat cloves, making it easy to slice and chop, or toss whole into the food processor for pesto, and it has a delicious mild flavor, perfect to use raw in a salad, salsa or guacamole. A good choice for those who want to eat raw garlic for various reasons but find the flavor of some other garlics too intense.
German White (Allium sativum): Also known as German Extra-Hardy, this hardneck porcelain garlic is one of the most popular varieties grown in the United States. It's easy to grow, cold hardy and disease-resistant, producing large, easy to peel cloves. It has a fairly basic flavor, not too hot or spicy, suitable for cooking and using raw in salads. Despite the name, the clove wrappers beneath the white outer skins are often pink.
When to Plant
Garlic is planted either in the fall or the spring, depending on your climate. In the north, plant garlic in the fall before the first frost. It is best to plant garlic in early spring in warmer climates, though seed garlic must be chilled first to break it out of its dormant state.
When planting in fall, start as soon as the soil temperature has dropped to 60 degrees Fahrenheit. If you wait too long, the roots will not be able to prevent the plants from heaving upward when the soil freezes. You can help to prevent heaving by covering the plants with 3 to 4 inches of straw mulch.
Selecting a Planting Site
Choose a site with full sun and moist, well-drained, loose, and sandy conditions. Loose soil lets the bulbs grow easily without rotting from heavier and wetter soil or damaging the papery skin that protects the garlic bulb from rot.
When selecting a site for planting garlic, make sure it has not had onions or other alliums growing there in the previous season, and, ideally, not for at least three years. You do not want your garlic to have to fight for nutrients with other alliums that may be still trying to grow.
Space, Depth, and Support
To plant, start by separating the garlic bulbs into individual cloves, leaving the papery layer around each clove intact. Choose the largest cloves for planting and use the smaller ones for cooking or preserving.
Dig holes in the ground that are around 2 to 3 inches deep to plant your garlic cloves. Space holes 4 to 6 inches apart. If planting in rows, space each row 2 inches apart. If you're tight on space, you can plant the cloves and rows closer together, but know that your bulbs will inevitably be smaller.
Plant the cloves 2 inches deep, placing each clove in its hole with the pointy tip facing up and the basal/root end facing down. Fill the planting hole with soil and pat it down gently. Top with 3 inches of mulch and water lightly. You should see garlic scapes emerge in about six to eight weeks.
How to Grow Garlic in Pots
If you want to try growing a hard-to-find garlic variety, try growing garlic in containers. Plant garlic in containers at the same time you would plant garlic in the ground: before the first freeze when the soil is cool. Choose a large container of any material with lots of drainage holes, or use a large grow bag. Fill it with high-quality potting mix, a slow-release fertilizer, and place cloves in the mix with the pointy end up. Keep the pot in a spot with six hours of direct sunlight, keep the soil moist but not soggy, and you'll be on your way to harvesting scapes and bulbs.
While it may be surprising for a plant that grows primarily underground, garlic loves light. To ensure the best chance at growing success, plant your garlic in a spot that receives full sunlight for at least six to eight hours a day.
One of the most important factors in successfully growing garlic is to start with nutrient-rich soil. It should also be moist but well-draining, with an ideal pH of 6.0 to 7.0. It helps to add a layer of mulch atop your soil after planting to safeguard the bulbs, conserve moisture, and prevent the growth of weeds.
True to its easy-going nature, garlic doesn't have a ton of water requirements. It generally likes its soil moist and should receive around an inch of water per week, with a slight increase if the weather is especially warm. Keep the soil evenly moist throughout the first part of the growing season, but allow the soil to go dry for two or three weeks before harvesting—if conditions are too wet near harvest time, mold can grow.
Temperature and Humidity
Garlic is a very hardy plant, and it actually grows best through the colder winter months. That being said, be sure to plant your garlic about a month before the first hard frost in fall. Additionally, garlic has no special humidity requirements; It is often already harvested before the peak of summer heat and humidity.
The use of fertilizer can be beneficial when growing garlic. Mix a slow-release organic fertilizer blend into your soil as you plant your garlic in the fall. Then, when the leaves begin to grow in the spring, feed the soil surrounding your plantings with a fertilizer blend high in nitrogen.
You'll know it's time to harvest your garlic when the majority of the bottom leaves have turned brown, which usually happens by mid to late summer, but you may be able to do this in the spring, too. Dig up a test bulb or two to determine maturity—the garlic should be well-wrapped but not split.
To harvest, push a garden fork straight down into the soil about 6 to 8 inches away from the plant. Angle the fork so that it goes under the bulb and lifts it out of the ground. Don’t pull the bulb out by its leaves, or you risk breaking the bulb off. Use caution because garlic bruises easily.
Brush off any soil clinging to the bulbs. Allow the bulbs to cure or dry for three to four weeks in either a well-ventilated room or a dry, shady spot outside. Once the tops and roots have dried, they can be cut off. You can also further clean the bulbs by removing the outer skins. Just be careful not to expose any of the cloves.
Harvested garlic likes to be stored in cool temperatures, as low as 32 degrees Fahrenheit. The softneck varieties may last up to eight months. Hardneck varieties may dry out, sprout or go soft within two to four months. Keeping hardnecks at 32 degrees Fahrenheit sometimes helps them survive for up to seven months without deteriorating.
Pruning and Propagating Garlic
Many garlic growers recommend cutting off the scapes, or topsets, of the garlic plants as soon as they start to curl, to conserve energy for the bulbs. Others prefer to leave the scapes intact because they feel it helps the bulbs in storage. Some take a middle-ground approach and cut off the scapes before they turn woody, when they are still good for cooking.
There is nothing easier to propagate than garlic. Simply put aside a few top-quality bulbs to plant in the ground or in a container the next season. Store bulbs for replanting at room temperature, with fairly high humidity of about 70 percent.
Garlic planted in the fall will naturally overwinter to be ready for a spring or summer harvest. The best way to overwinter your garlic plants is to water the plants well after planting and then cover them with 6 inches of straw mulch. The mulch will keep the ground moist, stop soil heave, and stop the growth of spring weeds.
Pests and Plant Diseases
While a fairly hardy crop, garlic does have to contend with a few pests and diseases throughout its lifespan.
Nematodes can be a chronic problem for garlic. These microscopic worm-like creatures live inside the garlic plant itself, eating it while reproducing. Nematodes don't need water to survive and can live in the surrounding soil for several years. A nematode infestation can build up for several seasons without much damage and then strike and take out an entire crop. To control nematodes, make an effort to plant clean stock, inspect growing plants frequently, and remove any plants that look diseased.
Onion thrips have also been known to plague garlic. Thrips have rasping-sucking mouth parts that first damage the leaves then suck up the seeping plant fluid. Severe damage can cause the garlic plant to wilt and die. To control thrips, keep areas free of moist, wet mulch that provides breeding areas, and trap the insects with sticky traps.
White rot fungus, which typically develops in the middle of the season, is among the most serious diseases garlic can face. It infects the plants, turning the leaves yellow and causing them to wilt and die back. As the roots rot, infected plants can uproot easily. Be sure you obtain cloves from certified disease-free stock because once a field has been infected with white rot fungus, it can take decades for the infection to completely clear.
Benefits of Garlic
The plant produces inhibitory effects on gram-negative germs of the typhoid-paratyphoid-enteritis group, indeed it possesses outstanding germicidal properties and can keep amoebic dysentery at bay. Garlic benefits also include anticancer activity.
Benefits of Garlic include reducing glucose metabolism in diabetics, slows the development of arteriosclerosis and lowers the risk of further heart attacks in myocardial infarct patients. Externally, the expressed juice is an excellent antiseptic for treating wounds.
There are two kinds of cholesterol. LDL cholesterol and HDL cholesterol. The former is bad for human health. Garlic is rich in the Ellison compound which effectively prevents LDL cholesterol from oxidizing. All those who have high cholesterol levels should include this herb in their daily diet.
Benefits of Garlic include fighting against thrombosis by reducing platelet aggregation for eye care. Garlic is rich in nutrients like selenium quercetin and vitamin C, all of which help treat infections and swelling.
Half the people in the world suffer from mild to severe forms of acne. Uses of Garlic include treating acne. Garlic may be used, along with other ingredients like honey, cream and turmeric, to treat acne scars and prevent the initial development of acne garlic acts as a cleanser and an antibiotic substance for soothing skin rashes.
Garlic protects our heart against cardiovascular problems like heart attacks and atherosclerosis. This cardio protective property can be attributed to various factors. With age, the arteries tend to lose their ability to stretch. Garlic, helps reduce this and may also protect the heart from the damaging effects of free oxygen radicals.
Daily use of garlic might reduce the frequency and number of colds. Its antibacterial properties, help in treating throat irritations. Garlic may also reduce the severity of up respiratory tract infections. Its benefits in disorders of the lungs like asthma, difficulty of breathing make it a priceless medicine.
Many researchers believe that obesity is a state of long-term low-grade inflammation. According to recent research, garlic may help to regulate the formation of fat cells in our body. This may help prevent weight gain.
Fresh garlic, garlic powder, and garlic oil are used to flavor foods.
Garlic may be used topically (applied to the skin).
Garlic cloves are used for consumption (raw or cooked) or for medicinal purposes.
Among the many garlic uses are in salad dressings, soups, stews, marinades, and much more.
Garlic is widely used for several conditions linked to the blood system and heart, including atherosclerosis (hardening of the arteries), high cholesterol, heart attack, coronary heart disease, and hypertension.
Garlic is also used today by some people for the prevention of lung cancer, prostate cancer, breast cancer, stomach cancer, rectal cancer, and colon cancer.