Image: Pereslavtseva Katerina/Shutterstock.comKnown by its scientific name Allium sativum, garlic is a considered a vegetable and is a member of the onion family, which also includes leeks, shallots, and chives. It is a staple in almost every cuisine on the planet and has been used for medicinal purposes for millennia. The Sumerians and Babylonians were fond of garlic, as were the Egyptians and Chinese. Scholars are divided as to whether garlic was first cultivated in the Mediterranean region as far back as 5,000 years ago, or in Asia, closer to China. A popular crop cultivated throughout the world, garlic also still grows wild in parts of Asia. China continues to dominate global production, though it is grown commercially in many countries including India, Bangladesh, South Korea, Egypt, and Spain. World exports are dominated by China, India, South Korea, Argentina, the Netherlands, and France. In the United States, production is led by California, where the town of Gilroy, in Santa Clara County, has been dubbed the garlic capital of the world. Other producers of note include Oregon, Nevada, New York, and Washington contributing to supply, though to a lesser extent. Since domestic production doesn’t come close to meeting demand, the United States is the world’s top importer of garlic from China, Argentina, and Mexico.
CULTIVATION Garlic grows best in well-drained soil with a high pH and concentration of organic matter. Soil must be tilled prior to planting to provide a loose growing bed for bulb development. Cloves are planted an inch or slightly more into the soil in the fall or early spring, with the pointed side up. Garlic is sometimes sprayed with sprout inhibitors during preharvest to help control development and lengthen the storage period. Garlic can be harvested at different times for specialty markets, but is generally harvested after the tops have fallen and are very dry. Early harvested young or immature bulbs, called green garlic, are mild in flavor and comparable to green onions. Bulbs should be dug up with roots and shoots attached and tied in bunches of 10 to 15. Pests & Diseases Leafminers are small black and yellow flies that damage garlic by feeding on plant sap and laying eggs within leaf tissue. The larvae then tunnel inside and may also hollow out the bulb. Damage is not a concern unless populations are so high they prematurely kill foliage. Natural enemies like wasps can reduce infestation. Several types of mites can affect garlic plants and the growth cycle. Bulb mites are shiny, white pests with four pairs of short brown legs. They appear in clusters on damaged areas under the root of the garlic bulb, stunt growth, and contribute to rot in stored garlic. They are most damaging during cool, wet weather. Other pests of concern include aphids, flies, leek moths, nematodes, onion maggots, various types of thrips, and wireworms. Waxy breakdown is a physiological disorder affecting the later stages of growth and associated with periods of high temperature near harvest time. Low levels of oxygen and inadequate ventilation may also contribute to the condition. This disorder is rarely seen in the field, and is most commonly found in stored or shipped garlic. Many types of rot can affect garlic and are primarily due to soil conditions; therefore, proper site assessment and crop rotation are necessary. Penicillium decay or rot (or blue mold) can be a common foe, characterized by lightweight bulbs and individual cloves that are soft and spongy. As the decay advances, cloves break down into a grey powdery mass. Storage in low humidity will help prevent this type of decay. Basal rot attacks plants already weakened by other diseases or insects, with symptoms including the yellowing and dieback of leaves, along with white fungal growth at the bulb base. White rot is similar to basal rot, but is more aggressive and the plant dies much faster. It can be devastating for growers if its spreads throughout a field, as it difficult to control. Symptoms include white, fluffy fungal growth and small, dark sclerotia. Downy mildew is common and can survive for years in the soil. It will kill younger plants and stunt the growth of older plants. Symptoms include whitish, furry growth on leaves, yellow discoloration, and blackened, shriveled necks with water-soaked scales on stored bulbs. Other diseases to look out for include anthracnose, botrytis neck or Rhizopus rot, damping off, leek yellow stripe virus, mosaic virus, types of rust, and Alternaria or purple blotch. The latter appears prominently on white garlic, on the outside skin, and can be remedied by removing the outermost layers.
Storage & Packaging
Because damage can occur during mechanical harvest, garlic is often harvested by hand, especially for sales to the fresh market.
It is sold as braided rope, individual bulbs, or by the pound with grocers often favoring larger bulbs.
Postharvest curing requires the bulbs and shoots be intact, hanging or spread across racks. The process should take place in a cool, dry place and once complete, bulbs can be stored for up to a year.
Temperatures between 30 and 32°F and relative humidity of 60 and 70% are optimal for storage. Freezing injury can occur at temperatures below 30°F.
References: Cornell University College of Agriculture and Life Sciences, Iowa State University Extension, PennState Extension, University of California Agriculture & Natural Resources, University of Minnesota Extension, University of Wisconsin-Madison.
GRADES & GOOD ARRIVAL
Garlic is graded as U.S. No. 1 and must be of similar varietal characteristics (as in all white or all red and not mixed), mature, well cured (not soft or spongy), and compact, with cloves that are well filled and fairly plump (not shriveled) and not shattered.
Cloves must also be free from mold and decay, as well as damage dirt, staining, sunburn, sunscald, cuts, sprouts, tops, roots, disease, insects, or mechanical injury.
Each bulb should be fairly well enclosed it its outer sheath, and unless otherwise specified, the minimum diameter of each bulb shall not be less than 1.5 inches.
• Poorly sheathed garlic is scored as a defect if bulbs are not fairly well enclosed and over 10% of the surface is exposed
• Sprouting is scored as a defect when any sprout is visible at the tip of any clove, even though it is not visible through the sheath
• Waxy breakdown progresses in storage to a deep yellow or amber color and can be translucent and sticky or waxy to the touch; unless in advanced stages, the bulb must be cut in half to detect its presence—score as a defect, as damage, when more than 10% of cloves are affected.
Source: Tom Yawman, International Produce Training, www.ipt.us.com.
Garlic Retail Pricing: Per Pound