USA plant library · vegetable

Radish

Raphanus raphanistrum subsp. sativus (Raphanus sativus) · Brassicaceae

Fastest vegetable (about 3-4 weeks) and great for kids

Photo: Self, en:Jengod, Public domain, via Wikimedia Commons

Sun: Full sun (tolerates part shade, but roots size up more slowly)
Soil: Loose, well-drained loamy or sandy soil
Soil pH: About 6.0-7.0 (neutral)
Water: About 1 in per week, with even moisture. Stress gives hot, woody or cracked roots
Hardiness: Cool-season annual (USDA zones 2-9). Bolts in heat
Height and spread: Garden radish foliage 4-12 in x 2-4 in; large (daikon) types and bolting plants can reach 3 ft

Guv's tipRadishes are quick: harvest 3-6 weeks after sowing. Keep moisture even, or stress gives you hot, woody or cracked roots.

Through the year

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Sow or plant

Harvest

Months are a rough guide. Time it by your own frost dates.

When to plant

Spring: Minnesota early Apr-early May, North Carolina mid Feb-early Apr, South Carolina coast Jan-Feb. Fall: Minnesota Aug, North Carolina Aug-mid Sep, South Carolina Sep-Oct/Nov. Sow every 1-2 weeks

Harvest or flowering

Harvest 3-6 weeks after sowing (spring and fall)

Pruning

Thin to 1-3 in apart (4-6 in for large types)

Making more plants

Seed, sown direct

Watch out for

Pest

Flea beetles

Look for: Small round shot-holes in leaves, worst in early spring

What to do: Row covers over seedlings; remove crop debris

Pest

Cabbage maggot

Look for: White maggots tunnel and groove roots; plants yellow, wilt or stunt

What to do: Floating row covers before adult flies emerge (not on previously infested soil); rotate crops; remove plant roots after harvest

Disease

Clubroot

Plasmodiophora brassicae

Look for: Swollen, stunted roots; wilting

What to do: Raise soil pH, long rotation away from brassicas

Disease

Black rot

Xanthomonas campestris pv. campestris

Look for: Yellow V-shaped lesions at leaf edges

What to do: Clean seed, rotation, remove debris

Always read and follow the label on any treatment, and check it is approved for use where you live.

Safety and spread

Pets and people: Low toxicity. May cause mild skin irritation (isothiocyanate). Radish roots are safe for dogs in small amounts. Not listed by the ASPCA

Weed risk: Not on the federal noxious weed list. The USDA PLANTS database shows no federal or state noxious or invasive status

Checked against two or more reputable gardening sources. How we check our facts

Growing somewhere else? See this plant for the UK.

Keep it by the back door

The Plant Doctor and the Guv's book

Printable pest and disease charts with real photographs, and all 50 USA plants in one book.

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