Colorado State University Extension Master Gardener in Larimer County
September 21, 2013
Ever thought about growing your own garlic? Fall is a great time to plant garlic in Colorado for harvest next summer and it’s easier to do than you may think. Local nurseries sell garlic in the fall for planting, and there are also many reputable online sources. Resist the temptation to plant cloves you purchase at the grocery store—they may not adapt to our cold climate and are often treated with growth inhibitors to prevent or reduce sprouting. Garlic can be self-sustaining: once you have grown garlic, you can use cloves to start the following year’s crop. Just remember to use the largest cloves.
There are three general types of garlic: softneck, hardneck, and elephant. These names are fairly descriptive as softneck has a flexible stalk that can be braided; hardneck has a more rigid stalk that cannot be braided; and elephant is super-large garlic. Softneck garlic has a shelf-life of about 6 to 8 months while hardneck can only be kept 3 to 5 months. Hardneck garlic has the most intense flavor, with softneck being milder, and elephant the mildest. Finally, hardneck has larger but fewer cloves than softneck and produces edible seed heads called scapes. Most grocery store garlic is softneck.
The best growing conditions for garlic include loose, well drained, amended soil; a sunny location; mulching for winter; and regular watering during extended dry periods. Slightly raised (2-3”) beds or mounds encourage better drainage during winter and summer.
You can plant garlic during October, while the soil can still be worked but when extended periods of extreme warmth are finished. Your garlic may sprout after planting but will re-sprout in the spring. Even if you see sprouts during a warm spell in February or March, garlic will survive additional snow and cold weather, finally sprouting “for real” in April or May.
When you are ready to plant, gently remove the outer wrapper (or skin) from the bulb and separate the head into cloves. Try not to bruise or squeeze the clove, and if possible don’t break the skins. Gently place each clove into the soil and cover with about 2” of soil. Plant cloves 6” apart with the pointy end facing up (i.e., root-end down). Each clove will produce a complete head of garlic. Label your garlic if you plant multiple varieties. One pound of cloves will produce about 10 pounds of garlic.
After planting your garlic, add about 2” of mulch (grass clippings work well). Mulch will help soil retain moisture, will reduce the effects of extreme temperature swings, and will suppress weeds, which compete with garlic for nutrients.
Water thoroughly after planting and weekly during fall. Follow a winter-watering schedule during extended dry periods in the winter. During the spring and early summer (until mid-June), water as often as required to prevent the soil from drying out without having it become water-logged. Fertilize once in the spring, no later than early May, with an all-purpose (10-10-10) fertilizer.
By mid-June, you will see scapes (seed heads) on your hardneck garlic. Remove the scapes (use in cooking as a garlic substitute) to encourage larger garlic. This is also the time to stop watering your garlic, about two to four weeks before harvest to allow the bulbs to develop a hard, dry skin.
Determining when to harvest is probably the trickiest part of the process, and every year is different based on weather conditions. If you harvest too early, the bulbs will be small and may not have formed wrappers but if you wait too long, the wrappers may be lost or split, which can result in rot, mold, or dehydration. A general rule of thumb is to harvest once the bottom three or four leaves are brown but the top leaves are still green. (Leaves turn brown starting at the bottom and work upward.) This will be sometime during the first two weeks in July, but may vary depending on variety. Each leaf represents a wrapper layer on the bulb, so if all the leaves turn brown, there will be no wrapper layers on the bulb. You can harvest a few bulbs to check whether it’s time to harvest—you should be able to see the shape of the individual cloves under the wrapper.
When harvesting, loosen the soil and lift garlic with a spading fork taking care not to puncture the garlic or damage the stem. Garlic can be easily bruised. Do not pull garlic out by the leaves. Gently brush any excess soil off the garlic – do not wash. Also, do not leave harvested garlic in the sun.
Immediately after harvest, “cure” garlic outdoors on mesh racks or by tying in bunches of 6 to 8 bulbs. Hang for 2 to 4 weeks in a well-ventilated location that’s out of direct sunlight and protected from rain. (Avoid too-cool or too-warm locations like basements and garages). You can tell when garlic is cured because the wrappers are papery, the leaves are brown and shriveled, and the roots are dry. Once cured, you can braid the softnecks or cut stalks to 1- 2” above the bulb, trim the roots, and gently remove any remaining dirt. Try to maintain the as many wrapper layers as possible on the bulb.
Store garlic for extended periods in a dry location with consistently cool (50 – 70 degrees) temperatures and plenty of air circulation. It’s better not to store garlic in the refrigerator unless you plan to use it immediately because conditions are generally too moist.
The author has received training through Colorado State University Extension's Master Gardener program and is a Master Gardener volunteer for Larimer County.
Larimer County is a county-based outreach of Colorado State University Extension providing information you can trust to deal with current issues in agriculture, horticulture, nutrition and food safety, 4-H, small acreage, money management and parenting. For more information about CSU Extension in Larimer County, call (970) 498-6000 or visit www.larimer.org/ext
Looking for additional gardening information? Check out the CSU Extension Horticulture Agent blog at www.csuhort.blogspot.com for timely updates about gardening around the state.
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Updated Tuesday, July 22, 2014