Radish planting dates by zone

Spring radishes, fall radishes, winter radishes

University of Minnesota Extension says radishes do best in cool conditions, tolerate cold weather, and are ready three to five weeks after planting. In summer heat, it says, they may flower and go to seed, turn too hot or become woody. University of Illinois Extension says early varieties grow best in the cool days of early spring, and that some later varieties can be planted for summer.

Winter radishes are a different crop. Illinois sows them in mid to late summer, as with fall turnips: they grow slower and larger, stay crisp longer, are usually more pungent and keep longer than spring radishes. Minnesota says daikon, the long white Asian radish, is often planted in late summer for a late fall harvest.

Sowing and thinning

The table dates spring sowing 4 weeks before each zone’s median last spring freeze, the offset our seed-starting tool uses. Illinois plants spring radishes from as early as the soil can be worked until mid-spring; Utah State University Extension plants 2 to 3 weeks before the last frost; Minnesota sows from early April through early May.

Sow little and often. Illinois makes short plantings every 10 to 14 days, Utah State every 10 days, and NC State Extension every 2 weeks. Illinois tucks radishes between slow crops such as broccoli, or into ground that will later take peppers, tomatoes and squash.

Minnesota sows small varieties one-fourth to one-half inch deep and larger ones up to one inch, about an inch apart, and loosens the soil at least six inches deep, a foot or more for long types. Thin early: Illinois thins spring radishes to 1/2 to 1 inch apart and winter radishes to 2 to 4 inches or more; Minnesota thins to about two inches, and four to six for daikon. UF/IFAS says not to transplant radishes, because it disturbs the root.

Water and soil

Radishes need to grow fast. Illinois says slow growth makes them hot and woody, and Minnesota that drought makes poor flavor and tough texture; it soaks the soil at least once a week without an inch of rain. Utah State says moisture swings crack the roots and make them hot and bitter.

Minnesota grows them in well-drained soil with a pH of 6 to 7 and warns against fresh manure, whose nitrogen can make the roots branch. NC State says radishes grow in full sun to part shade, but need at least 4 to 5 hours of sun or the roots take longer to size.

Planting for fall

Minnesota sows a fall crop from August 1 through September 1; Utah State starts fall plantings in mid to late August to avoid summer heat; NC State sows from August to mid-September in North Carolina. Texas A&M AgriLife sows fall radishes 1 to 8 weeks before the first freeze.

The table’s last fall sowing counts back 14 days from each zone’s median first fall freeze: our crop table’s 28 days from sowing to harvest less the 14 days of light frost radishes take. UF/IFAS says most varieties tolerate cool weather and will survive a freeze; Utah State harvests before heavy frosts or freezes.

Southern timing

NC State sows spring radishes from mid-February to early April in North Carolina. UF/IFAS grows them in Florida from September through March and names ‘Cherry Belle’, ‘Sparkler’, ‘White Icicle’ and ‘Champion’.

Texas A&M AgriLife’s home vegetable gardening guide sows radishes from 6 weeks before to 4 weeks after the frost-free date in spring and 1 to 8 weeks before the first freeze in fall, 1 inch apart in rows 14 to 24 inches apart, with 25 to 40 days to harvest.

Harvest

Pull radishes young. Minnesota harvests garden radishes three to five weeks after planting and says they turn fibrous and strong if left too long; UF/IFAS harvests 20 to 30 days after sowing; Utah State says most mature 25 to 45 days from seeding. Illinois says they stay in good condition only a short time before turning pithy and hot, and NC State says they are ready when the tops of the roots start to show above the soil.

Winter radishes are harvested larger. Illinois says they hold their quality in the garden for a long time in cool fall weather and can be pulled before the ground freezes. UF/IFAS harvests daikon after seven weeks in spring or ten in fall, and Minnesota spades or forks under long daikon roots so they do not break.

Common problems

All tops and no roots, Illinois and Utah State say, comes from sowing too thickly without thinning, weather too hot for spring varieties, or too much shade. Hot radishes come from slow growth or age, not size, Illinois says. Cracked and split roots come from age or a flush of water after a dry spell, Illinois and Utah State say.

Minnesota names flea beetles, worst on young spring plantings; cabbage maggots, which tunnel into the roots; and wireworms. NC State adds the swede midge, which crinkles the leaves, and lists radish as having low-severity poison characteristics: handling it may mildly irritate the hands. Minnesota names Alternaria leaf spot, black rot and clubroot.

Common mistakes

• Sowing too thickly and not thinning. Illinois and Utah State say crowded radishes make no roots.
• Leaving them in the ground. Minnesota says radishes left too long turn fibrous and strong.
• Spring varieties in summer. Minnesota says heat makes them bolt, turn hot or go woody.
• Letting the soil dry out. Utah State says moisture swings crack the roots and make them bitter.
• Sowing a whole packet at once. Illinois sows short rows every 10 to 14 days.

We found no radish source for South Carolina, Louisiana, Alabama or Mississippi that we read for this page. The Southern timing here is NC State’s, UF/IFAS’s and Texas A&M AgriLife’s.

Questions

When should I plant radishes in spring?

University of Illinois Extension plants them as early as the soil can be worked. The table on this page dates spring sowing 4 weeks before each zone’s median last spring freeze, from NOAA records.

How long do radishes take to grow?

University of Minnesota Extension says three to five weeks for garden radishes; UF/IFAS harvests 20 to 30 days after sowing. Winter radishes and daikon take longer.

Why are my radishes all leaves and no root?

Illinois and Utah State name three causes: seed sown too thickly and not thinned, weather too hot for spring varieties, and too much shade.

Why are my radishes so hot?

Illinois says the heat comes from how long radishes have grown, not their size: they grew too slowly or are too old. Utah State says heat stress adds to it.

When do I plant fall and winter radishes?

Minnesota sows fall radishes from August 1 to September 1, and Illinois sows winter radishes in mid to late summer. The table’s last fall sowing is 14 days before each zone’s median first fall freeze.

Sources

Freeze dates on this page are NOAA 1991–2020 Climate Normals, for every station the ZIP codes in each zone cite. Zones are the USDA Plant Hardiness Zone Map, 2023. The planting rules are named beside the table. Growing advice is quoted from the extension publications below, each written for its own area.

• University of Minnesota Extension, Growing radishes in home gardens , by Marissa Schuh and Jill MacKenzie (Reviewed 2024). Written for: Minnesota (USDA zones 3a–5a).
• University of Illinois Extension, Radish (Home Vegetable Gardening) . Written for: Illinois (USDA zones 5a–7a).
• Utah State University Extension, How to Grow Radishes in Your Home Garden , by Dan Drost (Published April 2020). Written for: Utah (USDA zones 4a, 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b).
• NC State Extension Gardener Plant Toolbox, Raphanus raphanistrum subsp. sativus (radish) . Written for: North Carolina (USDA zones 6b–9a).
• UF/IFAS Gardening Solutions, Radishes (Accessed October 2026). Written for: Florida (USDA zones 8b–11b).
• Texas A&M AgriLife Extension, Texas Home Vegetable Gardening Guide (EHT-077) , by Joseph Masabni (June 2014). Written for: Texas (USDA zones 6b–10b).

How we write our guides

Published October 29, 2026