When to plant

• Start seeds indoors about 10 weeks before planting out.
• Plant outdoors about 2 weeks before your average last spring frost.
• Ready to harvest about 110 days after planting out.

Plant in deep trenches or hill soil up to blanch stems.

Frost dates depend on where you live. Enter your ZIP code to get exact dates.

Dates by zone: 3a 3b 4a 4b 5a 5b 6a 6b 7a 7b 8a 8b 9a 9b 10a 10b

Growing basics

Harmful to pets. Every part is toxic to cats and dogs, raw or cooked. It damages their red blood cells.

Sun

Part sun (4–6 hours)

Spacing

6 in

Soil temperature

At least 45°F

Time to harvest

About 110 days

Containers

At least 3 gallons

Plant family

Onion family (alliums)

Harvest per plant

About 0.5 lb

Seeds keep

About 1 year

Companions

Keep apart: the bean and pea family (legumes). Onions and garlic can stunt beans and peas.

Keep apart: Asparagus. Onions and garlic can stunt asparagus.

Keep apart: Horseradish. Horseradish spreads aggressively. Give it its own spot.

Keep apart: Mint. Mint spreads aggressively into neighbors. Keep it in a pot.

Keep apart: Fennel (bulb). Fennel slows the growth of most garden plants. Grow it on its own.

Keep apart: Sunchoke (Jerusalem artichoke). Sunchokes spread aggressively and shade neighbors.

Pests and problems

Grow it well

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