Cultivated Garlic (Allium sativum)

How much light does a Cultivated Garlic need?

Full sun outdoors is what this plant needs, at least six hours of direct sunlight a day. A spot that gets at least six hours of direct sun daily meets this need. Full sun is the only light level recorded for this plant growing outdoors.

• Light: Full sun¹

How often to water a Cultivated Garlic

Garlic's water need is medium throughout its growing season. Soak the soil thoroughly whenever you water, reaching a depth of at least one inch. Plan on watering to this depth about once a week while the plant is actively growing, since that is when the one-inch guideline applies.

• Water: Medium²

Best soil for a Cultivated Garlic

Garlic does best in soil that drains well and still stays moist, not dry and not waterlogged. Good drainage is listed as a requirement for this crop. The soil's pH should sit somewhere in the neutral range of 6.0 to 8.0. A well-drained, moist bed with a pH in this range suits garlic. Both conditions are part of what this crop needs from its soil.

• Soil drainage: Well drained and moist^1,3
• Soil pH: pH 6–8¹

Hardiness and temperature

Garlic is hardy outdoors in USDA zones 4a through 9b. Garlic is a cool-season crop, growing best during cool weather. Below 20°F (-7°C), its foliage will likely take some damage. That is the specific cold threshold recorded for this plant's leaves. Zone 4a marks the coldest end of where it is listed as hardy outdoors, and zone 9b marks the warmest end of that same range.

• Hardiness: Zones 4a–9b¹
• Minimum temperature: 19.4 °F (-7 °C)⁴

Fertilizing a Cultivated Garlic

Garlic is described as a moderate to heavy feeder. Apply nitrogen fertilizer at planting, and again once the shoots reach about 4 to 6 inches tall. It's also recommended before fall planting, in April, and again in late May if needed.

• Fertilizer: Heavy feeder (Mar–May)^5,6,7

Pruning a Cultivated Garlic

Garlic produces scapes, its flower stalks, that rise above the leaves in June. Growers typically cut off these scapes, a practice recorded for May and June. Removing the scape is the deadheading step listed for this plant. The scapes emerge through the top of the foliage as they grow.

• Pruning: Deadheading (May–Jun)⁸

How to plant a Cultivated Garlic

This crop can be planted outdoors anywhere within USDA hardiness zones 4a to 9b. Mature plants spread about 8 to 12 inches (20 to 30 cm) wide. Leave that much room between plants when you set them in the ground. Plant cloves outdoors about 7 to 14 days after the first killing frost.

• Hardiness: Zones 4a–9b¹

Winter care

Cold hardiness for this crop runs from USDA zone 4a up to zone 9b. Its leaves are likely to show damage once temperatures fall under 20°F (-7°C). Outside that zone range, garlic is not listed as reliably hardy outdoors in winter. Garlic is also fertilized before this fall planting, as part of its feeding schedule. Garlic is classified as a cool-season crop.

• Hardiness: Zones 4a–9b¹
• Minimum temperature: 19.4 °F (-7 °C)⁴

When to plant Cultivated Garlic

Direct-sow garlic cloves outdoors one to two weeks after the first killing frost each fall. Allow about 90 to 100 days to maturity from transplanting. Harvest typically falls in late June or July.

• Direct sow: 1–2 weeks before first fall frost²

When and how to harvest Cultivated Garlic

Harvest garlic between late June and late July. Begin harvesting once the lower leaves have turned brown while about half or slightly more of the upper leaves are still green. Days to maturity for garlic run about 90 to 100 days after transplanting.

• Harvest: lower leaves have turned brown while about half (or slightly more) of the upper leaves remain green (Jun–Jul)³
• Days to maturity: 90–100 days from transplant⁹

How to propagate a Cultivated Garlic

Garlic is propagated by planting individual cloves, called offsets, separated from the bulb. Space the cloves about 6 to 8 inches (15 to 20 cm) apart. Plant them about 2 to 3 inches (5 to 8 cm) deep. Offsets are the only propagation method recorded for this plant.

• Propagation: Offsets¹

Common problems

Garlic can be affected by several pests, including bulb mites, onion maggot, onion thrips, allium leafminer, and stem and bulb nematode. Onion maggot bores into the stems, which can turn the plant yellow and make it wilt. Diseases recorded for garlic include bulb rot, white rot, basal rot, gray mold, and aster yellows. Bulb rot tends to occur when the soil stays too wet.

• Common pests: bulb mites, onion maggot, onion thrips, allium leafminer and stem and bulb nematode^1,3
• Common diseases: bulb rot, white rot, basal rot, gray mold and aster yellows¹

Questions and answers

Is garlic toxic to cats and dogs?

Yes, garlic is toxic to both cats and dogs. The ASPCA lists it as toxic to both animals. No severity level is stated for cats.

How much sun and water does garlic need?

Garlic needs full sun outdoors, meaning six or more hours of direct sunlight a day. Its water need is medium, with at least one inch of water each week during the growing season.

When should you harvest garlic?

Harvest garlic between late June and late July. Begin once the lower leaves have turned brown while about half or more of the upper leaves are still green.