🌱 Free USDA zone, frost dates & planting calendar, by ZIP About & data sources
My Planting Zone know your zone

Plant Radishes in Zone 7b

Seed-starting, transplant & harvest dates for USDA Zone 7b

Direct sow
Mar 6
Harvest (~28d)
Apr 3

Zone 7b averages 212 frost-free days, running from a last spring frost around April 3 to a first fall frost around November 1. Radishes needs roughly 28 days from planting out to first harvest, so it uses about 13 percent of that window. Radishes is a hardy crop, which is what decides where in the window it belongs.

Radishes handles cold soil, so there is no reason to wait for the frost date. Direct sow around Mar 6, roughly 4 weeks before the Zone 7b last frost, as soon as the ground is workable. Sowing at the last frost instead costs you the coolest and best part of the season. At 28 days to harvest, a 212-day Zone 7b season has room for about 5 sowings, so stagger them rather than planting everything at once.

Planting radishes for a fall harvest in Zone 7b

Yes. Sow radishes by October 11 in Zone 7b. That is 21 days before the average first frost, which covers the 28 days to maturity plus about two weeks for the slower growth that comes with shortening days, minus the roughly 21 days radishes keeps going once light frost arrives.

Radishes are the fastest fall insurance crop. Fall roots stay milder and split less than spring ones because the soil is cooling rather than heating.

Fall sowing opens
Sep 20
Sow by (last chance)
Oct 11
Fall harvest
Nov 8

Fall dates are counted backward from the Zone 7b average first frost, not forward from a sowing date. See the fall planting calendar by zone for the full method.

Spring vs fall radishes in Zone 7b

Planting Sow or start In the ground Harvest
Spring Mar 6 Mar 6 Apr 3
Fall by Oct 11 Oct 11 Nov 8
Last spring frost
Apr 3
First fall frost
Nov 1
Growing season
212 days

Radishes in nearby zones

Further reading on radishes

Other crops in Zone 7b

Frequently asked questions

When should I start radishes in Zone 7b?

Direct sow outdoors around Mar 6.

Can I direct sow radishes in Zone 7b?

Yes, direct sow around Mar 6.

Can I plant radishes in the fall in Zone 7b?

Yes. Sow radishes by October 11 in Zone 7b. That is 21 days before the average first frost, which covers the 28 days to maturity plus about two weeks for the slower growth that comes with shortening days, minus the roughly 21 days radishes keeps going once light frost arrives.

Will radishes survive frost in Zone 7b?

Radishes is a hardy crop and keeps going roughly 21 days past the first light frost in Zone 7b. A row cover or a straw mulch buys more.

How many plantings of radishes fit in a Zone 7b season?

About 5. Zone 7b averages 212 frost-free days and radishes needs roughly 28 days plus a couple of weeks of turnaround, so sowing every 21 days keeps a supply coming.