Growing garlic in the home garden opens up the opportunity to experience an array of flavors that you will never find with store-bought garlic. Growing garlic is easy, but there are a few important things to know to have success. To share his expert advice on growing great garlic, my guest this week is Alley Swiss of Filaree Farm in Washington.
Alley has owned Filaree Farm since 2010, and the farm has been growing organic seed garlic since 1977, serving gardeners, nurseries, and commercial growers. Filaree Farm also stewards the largest collection of garlic in North America with more than 100 strains of garlic — from heat-loving varieties, such as Creole and turban garlic, to cold-hardy varieties, such as porcelains, elephant garlic and purple stripes.
While most of us are used to the white California or Chinese garlic from the grocery store, there is a whole world of colors, shapes and flavors to explore. And because garlic is easy to save to grow again, anyone with just a little knowledge about growing food can participate in the cycle of saving seeds, Alley says.
For a comprehensive guide on growing garlic, you can download my free resource, Grow Great Garlic at Home. It has everything you need to know to pick out, plant, care for, harvest and cure garlic successfully.
Great Conditions for Garlic
Filaree Farm is located in North Central Washington State in the Okanogan Valley, where the summers are hot and dry and the winters are quite cold. It’s 200 miles from the West Coast and just 50 miles south of the Canadian border. The crops are watered from streams that are fed by Cascade Mountains snowpack.
“It’s a really great climate to grow garlic, and I don’t think there would be any other location in the country where we could grow as many varieties as we’re able to grow here,” Alley says.
Understanding Seed Garlic
What we call “seed garlic” is not true seed. Garlic varieties that are genetically close to wild garlic can still produce true seed if allowed to flower, but outside of a highly controlled setting like a lab, it is very difficult to successfully grow garlic from true seed, Alley says.
Seed garlic is a bulb of garlic divided into cloves. Each clove planted produces a clone of the parent, and the cycle can be repeated endlessly year after year. Alley notes that garlic is always a living plant. That bulb harvested in summer is alive when it is cured and stored in anticipation of planting cloves in fall.
When garlic is repeatedly planted in the same garden for years, it adapts to the climate and soil conditions, becoming the best crop that it can be. That means that the third or fourth generations of garlic will perform better than the cloves that were planted in the first year.
Garlic that is unhappy in its growing conditions will likely produce a small bulb that separates into individual cloves. Those small cloves can be planted to produce more substantially sized bulbs a generation or two later. Another symptom of unhappy garlic is when a bulb does not produce cloves. This is called a “round,” and it makes great seed garlic because it has so much energy stored in the bulb, Alley says.
Hardneck Garlic vs. Softneck Garlic
All garlic fits into one of two categories: hardneck and softneck.
Hardneck garlic has a scape, which is a flower stalk that starts in the center of the bulb. It makes the bulb’s stem hard — hence, hardneck. The scape can be harvested before it flowers and used in garlic scape pesto or any number of recipes. In fact, it is important to cut off the scapes so the plant puts its energies into producing a large bulb rather than producing a seed head. Cut off the scape right above the top leaf of the plant once the scape has curled, forming a “P” shape.
Softneck garlic does not have a scape, so its stem is soft enough to be braided. Softneck garlic is also easier to grow and stores better than hardneck garlic, but softneck garlic performs better in the South and hardneck garlic does better in the North. However, Alley says softneck can be grown anywhere and there are some hardneck varieties that can perform quite well in hot climates.
Garlic Varietal Groups
Purple stripe is a group of hardneck garlic that includes the extremely popular Chesnok Red, which is a standard purple stripe that is easy to grow with tremendous flavor and beautiful coloration. Glazed purple stripe has bulb wrappers that are more silvery, and marble purple stripe is very cold-hardy.
Porcelain is a hardneck group that grows large cloves and tall plants — as much as 4 or 5 feet tall. Rocambole is a storied hardneck group that includes Spanish Roja, which is said to have the truest garlic flavor of all varieties.
Creole is a group of heat-loving, red-cloved garlics that are phenomenal for storage. Creoles can be either hardneck or softneck.
The Asiatic group and the turban group from Southeast Asia also contain both hardneck and softneck varieties.
The softneck garlic groups are artichoke garlic — named for the layers that the cloves form in — and silverskin garlic, which is what you are most likely to find in the grocery store. Silverskin is the group to look for if your goal is long-term storage.
Food Garlic vs. Seed Garlic
Garlic bought at the grocery store is designed to be eaten, not planted, so it was raised differently than seed garlic. Food garlic may also be treated to prevent sprouting to increase its shelf life. If planted, food garlic may simply rot.
Seed garlic must be free of garlic pests and diseases to ensure customers will have a healthy, vigorous crop. A key to producing good seed garlic is frequent roguing. Roguing is the practice of removing plants that show undesirable traits or signs of disease or insect pressure. “We just dig those up and take them right out of there because we don’t want to pass on any of those things,” Alley says.
Alley says Filaree Farm rotates its fields on a seven-year rotation. That means garlic is only planted in the same place once every seven years, and on the other six years that location is fallow or under a cover crop to restore nutrients to the soil. Rotating crops reduces the presence of garlic pathogens in the soil and also prevents pest populations from building up.
Organic Seed Garlic vs. Conventional Seed Garlic
Seed garlic that is conventionally grown may be grown with synthetic fertilizers and routinely sprayed with chemical pesticides and fungicides. Organic garlic is grown in healthy, nutrient-rich soil and is adapted to resist pest and disease pressure and to outcompete weeds. Simply, organic garlic is easier to grow in the home garden without chemical interventions.
Garlic Pests & Diseases
A number of years ago, an outbreak of harmful nematodes in the Northeast posed a big problem for garlic growers. The nematodes were traced back to a large-scale seed producer in Ontario, Alley says. He adds that in the West, nematodes have not been a problem, but elsewhere gardeners should keep an eye out.
Otherwise, garlic is generally unbothered by pests. In fact, groundhogs, squirrels and rabbits all avoid garlic.
Basal rot, a Fusarium fungus, is a disease that affects the plant starting at the bottom of the bulb. That brown spot on the underside of the bulb where the roots grow from is called the basal plate. Fusarium is present in all soils, and certain garlic varieties, such as those in the Rocambole group, are more susceptible to it than others. Basal rot is common in very wet conditions, so having well-draining soil is essential.
To control soil-borne diseases such as Fusarium, the best thing to do is to practice crop rotation, according to Alley. After planting garlic in a particular location, do not plant anything from the allium family — garlic, onions, shallots, scallions, leeks, chives — in that spot for the following two years. Alley recommends a rotation schedule of at least three years if not seven or 10 years.
How to Plant & Fertilize Garlic
In northern climates, the time to plant garlic is in the fall, and many growers in southern climates will also plant at this time. In general, the appropriate planting time is two to three weeks before the first hard freeze — around mid-October for most people. If you don’t have a hard freeze, wait until late November.
The downside of planting too early is you may get a lot of top growth before a freeze, Alley explains. That freeze, if sudden, can ride the foliage down to the clove and damage the crop. Just two to three weeks of root growth before a freeze, with minimal or no top growth, is the goal.
Garlic prefers soil with a pH of 6.5-6.7, which is just slightly acidic. Mulching with leaves or straw is highly recommended in northern climates to protect cloves from sudden swings in temperature.
If you have good soil that is well amended with compost and/or manure, you don’t need to add any fertilizer. However, if you feel like your garlic needs a boost, the best time is during the rapid growth that comes in spring. When the first sprouts come up in early spring through the bare ground or mulch, you can start fertilizing with a heavy nitrogen fertilizer. Filaree Farm uses a foliar spray of fish-seaweed emulsion and also uses organic calcium. “Garlic loves calcium,” Alley notes.
Nitrogen fertilizer can be applied once every week to 10 days throughout the early growth of the crop. Around May, when the garlic begins to bolt, it’s time to stop fertilizing. If you keep applying fertilizer at this stage, the plants will have tall stems instead of big bulbs.
When to Harvest Garlic
To know when garlic is ready for harvest, watch the leaves. The leaves will begin to turn brown, starting from the bottom of the plant. When half of the leaves have become brown and crispy and the top half remains green, it is time to harvest. Once a plant is harvested, each of the remaining green leaves will dry out into a storage wrapper to better protect the bulb.
Another way to tell if garlic is ready is to dig down to inspect the top of the bulb. If the bulb doesn’t have a good amount of shoulder, it is not ready.
During the later stage of bulb development, water every other week instead of every week. And within three weeks of harvest, completely cut off watering. You want there to be moisture way down deep in the root zone, but not surrounding the bulb itself. Excess water can invite diseases and stain the wrappers.
How to Cure & Store Garlic
After digging up garlic, leave the bulbs attached to the stems and roots until the bulbs have had a chance to cure. Place the garlic on racks or hang in bundles in a shed, a garage or a barn with plenty of airflow for three weeks. After that time, the tops can be cut off and the bulbs can be stored. The bulbs should feel bone dry at this stage. If the first bulb tested is not dry, give the rest of the bulbs more time before clipping off the tops.
Optimal conditions for garlic storage are about 65% humidity in a dark place. “So not super humid, but not totally dry either,” Alley says. Temperature between 50° and 60° is best. Depending on the variety and storage conditions, garlic can be stored for between four months and a year.
I hope that you will have more confidence growing garlic after listening to my conversation with Alley Swiss. If you haven’t listened yet, you can do so now by clicking the Play button on the green bar near the top of this post.
What is your favorite type of garlic to grow? Let us know in the comments below.
Links & Resources
Some product links in this guide are affiliate links. See full disclosure below.
joegardener Online Gardening Academy™: Popular courses on gardening fundamentals; managing pests, diseases & weeds; seed starting and more.
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joegardener Online Gardening Academy Perfect Soil Recipe Master Class: Learn how to create the perfect soil environment for thriving plants.
joegardener Online Gardening Academy Beginning Gardener Fundamentals: Essential principles to know to create a thriving garden.
joegardener Online Gardening Academy Growing Epic Tomatoes: Tomato expert Craig LeHoullier joins me in leading this course on how to grow healthier, productive tomato plants and how to overcome tomato-growing challenges.
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