Vegetable · Amaryllidaceae
Garlic
Allium sativum
Tuck a clove into the ground come fall and let it work all winter, and a single clove swells into a whole head by summer.
Full sun
Every 3–7 days
240–270 days
USDA 3–8
Overview
Few crops repay you like garlic does for so little effort, and that bargain hooks you fast. Bury one clove in autumn soil; over roughly eight or nine months it anchors down through the cold, sends up green blades when spring arrives, and bulks into a fat head by the height of summer. Garlic belongs to the onion family, and you taste that kinship in the sharp bite it lends a dish as much as you see it in the flat foliage.
Growers pick a camp. Hardneck kinds throw a rigid center stalk crowned by a looping flower stem, the scape, sit in storage a few months, and barrel through brutal winters. Softneck kinds skip that stalk, load extra cloves into each bulb, hang on in storage much longer, and braid up neatly, all of which points them toward gentler regions.
Nothing hurries garlic along, and coming to terms with that pays dividends. A real winter chill has to split the clove before it can build a proper head, which puts the season, rather than your labor, in charge of the pace. Line the timing up and everything else comes down to mulch, a spring feed, and patience.
Care
The short version: set your fattest cloves into loose, fertile, well-drained soil and full sun in fall, hold the bed evenly moist as spring growth takes off, push nitrogen early, then dial back the water so the bulbs cure up for harvest.
Light
Garlic thrives on full sun, ideally 6 or more hours a day, to pump up a big bulb. It scrapes by in partial sun, but the heads shrink and the plants come out weaker.
Water
Hold the soil evenly moist as spring growth surges, roughly an inch of water a week, and never let it turn waterlogged. Then back off and cut the water in the last 2 weeks before harvest, which drives the bulbs to cure and store well.
Soil
Set the cloves into loose, fertile, well-drained loam packed with organic matter, at a pH between 6.0 and 7.0. Where your ground runs to heavy clay, build a raised bed and keep the bulbs from rotting in soggy soil.
Temperature
Garlic shrugs off a wide range, from about 14°F to 86°F (-10°C to 30°C), and it counts on a real winter chill to break a clove into a full head. That cold stretch is exactly why the cloves go down in fall.
Humidity
Everyday outdoor humidity treats garlic just right, so there's no number to chase. Good airflow counts for more, since damp, crowded leaves roll out the welcome mat for rust and other fungal trouble.
Feeding
Dig compost or a balanced fertilizer through the bed when you plant in fall, then come spring, side-dress with nitrogen as the young leaves climb. Halt the feeding the moment bulbing kicks off, right around scape emergence, or the plant spends itself on foliage and shortchanges the bulb.
Pruning
Garlic asks for next to no pruning. On hardneck types, snap off the scapes soon after they rise and curl, so the plant channels its energy into the bulb rather than the flower stalk, and the scapes make fine eating on their own.
Size & spacing
Plants climb to 12 to 24 inches (30 to 60 cm) tall on narrow upright leaves. Space the cloves 6 to 12 inches (15 to 30 cm) apart so each one has room to bulk up and air can slip between them.
When to plant
The calendar drives garlic, and that rhythm works in your favor. Sink the cloves during fall, 4 to 6 weeks before the ground freezes, and roots grab hold ahead of winter. Cold weather handles the heavy lifting from there; pull your bulbs come mid to late summer once those lower leaves brown out.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Plant: Fall, about 4-6 weeks before the ground freezes (typically late September through November depending on region), so cloves root before winter
- Harvest: Hardneck scapes appear in early summer and are removed; harvest bulbs in mid-to-late summer when the lower one-third to one-half of the leaves have yellowed and browned
Hardiness
USDA hardiness zones: 3–8
Temperature: down to -40°C
Troubleshooting
Garlic tells on itself, either up top in the leaves or down in the bulb you finally uncover at harvest. Spot the leaf signals early and you can often rescue the crop, while bulb rots demand a quick lift. Find your symptom below, then jump on the cause before it travels down the row.
Yellowing plants sporting white fuzz and tiny black flecks at the bulb
You are looking at white rot, a soilborne fungus that eats the bulb and can lurk in the ground for decades, primed for the next allium. Nothing saves it mid-season, so dig out the hit plants along with the soil around them and bin the whole lot rather than composting. Its slower twin is fusarium basal rot, which paints a pinkish-white stain but skips the poppy-seed black sclerotia.
Fix:
- Remove and destroy infected plants and surrounding soil; do not compost
- There is no effective in-season chemical rescue for home gardens
Rusty orange bumps popping up on the leaves
Those raised orange pustules spell garlic rust, a fungus that thrives in cool, humid, crowded plantings and puffs powdery spores when you rub a leaf. Pull the worst foliage and open up the spacing so air can dry the blades. Should it strike late in the season, harvest early, because the bulbs down below still eat just fine.
Fix:
- Remove heavily infected foliage
- Harvest promptly if infection occurs late in the season; bulbs are still edible
Runty bulbs that never break into cloves
A bulb that stays tiny or refuses to divide almost always skipped its cold winter, planted too late in fall or shoved in during spring without enough rooting and chill. Weeds elbowing in on the sparse upright leaves and a missed spring nitrogen feed only pile on. Cook the runts, then set your biggest cloves 4 to 6 weeks before the ground freezes next round.
Fix:
- Use undersized bulbs in the kitchen; they are edible
- Adjust planting date and fertility the following season
Silvery streaks and a gray cast on the leaves in hot weather
Silvery flecking that spreads through hot, dry spells flags onion thrips rasping away at the leaf tissue. Part the leaves and hunt the folds for tiny slender yellow-brown insects, or rap the foliage over white paper and watch them drop. Blast them off with a strong jet of water, grab insecticidal soap when the damage runs heavy, and keep the plants watered through the dry stretches.
Fix:
- Knock populations down with a strong spray of water
- Use insecticidal soap if damage is heavy, ensuring coverage in leaf axils
Toxicity
People treasure garlic in the kitchen, yet it turns truly hazardous for animals. Those same organosulfur compounds that build its flavor go on to wreck red blood cells in cats, dogs, horses, livestock, rabbits, and birds alike, sparking hemolytic anemia whether raw, cooked, or dried to powder. No creature suffers worse than a cat, and ounce for ounce garlic beats onion, so shut every scrap of it far from your pets and stock.
Toxic to
Cats · Dogs · Horses · Rabbits · Livestock · Birds
Safe for
People
Cats Severe
Vomiting, diarrhea, drooling, lethargy, weakness, pale gums, a racing heart, quickened breathing, red or brown discolored urine, and collapse from hemolytic anemia; cats react hard even to small amounts.
Dogs Moderate
Vomiting, diarrhea, belly pain, lethargy, weakness, pale gums, a faster heart and breathing rate, and red or brown urine; large or repeated doses can drive severe hemolytic anemia.
Horses Moderate
Weakness, lethargy, pale mucous membranes, and discolored urine from hemolytic anemia after a horse takes in a meaningful amount.
Rabbits Toxic
Garlic has no business in a rabbit's diet. The same organosulfur compounds that hammer cats and dogs go after a rabbit's red blood cells, and no amount is safe to offer, so keep every form far out of reach.
Livestock Toxic
Cattle, sheep, goats, and horses that graze garlic or its trimmings can slide into hemolytic anemia, showing weakness, a dull manner, pale gums, and dark, discolored urine. Fence stock clear of the bed and never toss them allium scraps.
Birds Toxic
Garlic is unsafe for birds, backyard poultry and pet parrots alike. Even small amounts chip away at their red blood cells over time, so keep bulbs, cloves, and seasoned scraps out of reach.
People Safe
Garlic is a kitchen mainstay and safe for people to eat, raw or cooked. The toxicity that endangers animals carries no such threat for people, so cook it up and enjoy it freely.
Store bulbs, peeled cloves, garlic powder, and garlic-seasoned foods where pets cannot reach them; fence or cover garden beds, and never feed pets table scraps containing garlic or onion. Signs of anemia can be delayed several days after ingestion.
Helpline numbers
United States
ASPCA Animal Poison Control: (888) 426-4435 (fee applies)
United Kingdom
Animal PoisonLine: 01202 509000 (fee applies)
Australia
Animal Poisons Helpline: 1300 869 738
Varieties
Hundreds of garlic cultivars are out there, and they all fall into a handful of familiar hardneck and softneck types. Here are the ones that will land in your garden most often.
Music
A hardneck porcelain type packing 4 to 6 big, peel-in-a-flash cloves per bulb that laughs off hard winters, making it a rock-solid pick up north.
German Extra Hardy
A hardneck porcelain type prized for powering through cold winters and for its bold, full-bodied flavor.
Inchelium Red
A softneck artichoke type with a mild flavor and loads of cloves that shines in milder climates and braids up beautifully.
Silver Rose
A softneck silverskin type with rose-tinted cloves that outlasts nearly every other garlic in storage and stays a go-to for braiding.
Companions
Garlic earns its keep as a neighbor, since its sulfur compounds help drive off aphids and other soft-bodied pests, but it sets back the legumes, so keep it clear of beans and peas.
Plant near
roses: Garlic's sulfur compounds are reported by extension sources to help deter aphids and other soft-bodied pests around roses
brassicas (cabbage family): Interplanted garlic can help repel some cabbage-family insect pests
carrots: Garlic may help deter carrot pests such as rust fly, and the crops do not compete strongly
Keep apart
beans: Alliums are reported to inhibit the growth of beans and other legumes
peas: Alliums are reported to inhibit the growth of peas and other legumes
How to propagate
Garlic keeps multiplying from its own cloves, which makes starting a new crop about as easy as gardening gets, though it rewards you on its own unhurried timeline.
Bulbs & cormsEasy
Fall, 4-6 weeks before the ground freezes · Roots establish in 4-8 weeks before the ground freezes; bulbs are ready to harvest about 8-9 months after planting
Cloves, not seed, start your garlic, so break a bulb apart just ahead of planting and keep each clove's papery jacket on. Point the fattest cloves upward and press them about 2 inches deep, spacing them 4 to 6 inches apart, 4 to 6 weeks before the ground freezes. Lay mulch once the soil chills, and the cloves anchor down over the next month or two heading into winter. Patience buys the whole thing, because you won't lift a bulb until 8 to 9 months later, in mid to late summer. Those little topset bulbils riding hardneck scapes will grow on too, though they need 2 to 3 seasons to reach full-bulb size.
Myths
Garlic makes a safe, natural flea and tick remedy for dogs and cats.
This one is flat-out dangerous. Garlic poisons cats and dogs in every form, since its thiosulfates wreck red blood cells and can spark Heinz-body hemolytic anemia, and cats catch it worst. No dose is safe or proven against parasites, so grab a vet-approved product instead.
Grocery-store garlic works fine as planting stock.
Supermarket garlic often carries sprout inhibitors, can pack disease, and usually turns out to be a variety that never fit your climate. Plant certified disease-free seed garlic from a solid supplier and you start clean.