General
Garlic is a hardy Allium grown primarily from cloves. Softneck types (braidable, good storage) and hardneck types (produce edible scapes, better cold tolerance) both perform well in cool climates. Autumn planting is standard in cold regions for larger bulbs; spring planting is possible if cloves have vernalized (at least 30–60 days below 10°C). Garlic prefers full sun, fertile, well-drained soil, and consistent moisture without waterlogging. In Sweden, it overwinters reliably in zones 1–7 with mulch. Expect plant height 30–60 cm, with scapes on hardneck types reaching higher.
Light
Full sun (6–8+ hours of direct light).
Soil type
Well-drained loam or sandy loam enriched with mature compost; avoid heavy, waterlogged clay.
Water requirement
Moderate. Keep evenly moist during establishment and bulb formation; reduce watering 2 weeks before harvest.
Nutrient requirement
Medium. Nitrogen early for leaf growth, then balanced nutrition; avoid fresh manure.
Precultivation
Pre-starting is optional. For spring crops in cold areas, you can pre-sprout cloves in modules: chill seed garlic 4–8 weeks at 0–6°C if not already vernalized, then pot individual cloves tip-up in 7–9 cm cells with free-draining mix in mid-Feb to mid-Mar. Keep cool-bright (5–10°C) to avoid legginess; harden off before transplanting once soil is workable. Do not overwater—lightly moist is enough until roots anchor.
Planting
Choose the sunniest, well-drained bed. Work in 2–3 cm of mature compost and a light, chloride-free potassium source if soil tests are low; avoid fresh manure. Break bulbs just before planting; select the largest, healthy outer cloves. Plant tip up, 4–6 cm deep (6–8 cm in colder, lighter soils), spacing 10–15 cm in-row and 25–30 cm between rows. Mulch 5–10 cm with straw/leaves after planting, especially for autumn plantings, to buffer frost heave and suppress weeds. Maintain pH 6.0–7.5. Rotate: do not plant after onions, leeks, or garlic for at least 3–4 years.
Pruning
No true pruning. For hardneck types, remove scapes when they make the first loop (usually June–mid July) to direct energy to bulbs; harvest scapes tender and use in the kitchen. Avoid removing healthy leaves, as leaf area determines bulb size.
Maintenance
Weed carefully; garlic dislikes competition. Water regularly during leaf expansion and bulb formation (late spring to early summer). Side-dress with nitrogen in early spring when growth resumes, and once more 3–4 weeks later; stop nitrogen by mid-June to promote curing. Maintain mulch for moisture and weed control but keep it airy to prevent rot. Protect from onion fly/leek moth with insect netting. Favor wide spacing and good airflow to limit rust; remove heavily infected leaves and avoid overhead irrigation. In wet climates, raised beds improve drainage.
Harvest
Harvest when 30–50% of leaves have yellowed and the remaining leaves are still green—often mid Jul to late Aug for autumn plantings. Lift gently with a fork; do not pull by the tops. Cure bulbs in a dry, shaded, well-ventilated place for 2–4 weeks until necks are dry and skins papery. Trim roots and tops (or braid softnecks). Store culinary garlic cool and dry at 10–20°C with low humidity and airflow; for seed garlic, store cooler near 0–4°C to prevent premature sprouting. Do not wash bulbs—brush off soil.
Common issues
• Bolting (softnecks) or small bulbs: insufficient vernalization, late planting, shade, or nitrogen too late. • Rust (Puccinia allii): worsened by dense canopies and overhead watering; use spacing, resistant varieties, and remove infected debris. • White rot/fusarium: avoid waterlogged soil; strict rotation 4+ years; plant clean stock. • Onion fly/leek moth: use fine insect netting; remove crop residues. • Split bulbs or poor storage: overwatering late, harvesting too late, or curing in humid conditions.
Rotation schedule
Rotate Alliums on a 3–4 year cycle minimum. Follow garlic with legumes or leafy greens; avoid following or preceding with onions, leeks, chives, or shallots. Incorporate a fertility-building cover crop (e.g., clover or a winter-killed oat/pea mix) in the off years.
Pollination
Not applicable (vegetative propagation from cloves).
Companion plants
Carrot, beet, lettuce, strawberries, tomatoes, roses, fruit trees; herbs like dill and chamomile.
Incompatible plants
Beans and peas (can stunt legumes); avoid planting with other Alliums in the same bed concurrently.
