Kentucky planting calendar

When to plant radishes in Kentucky — sow, transplant & harvest dates

Kentucky is mostly USDA zone 6b (range 6a-7b). Dates below are derived from radishes's frost tolerance and Kentucky's frost window — not generic national averages.

Radishes planting timetable for Kentucky

Stage	When in Kentucky	Anchor
Direct-sow outside	late March (March 25)	21 days before the last frost (mid-April)
First harvest (estimate)	late April (April 22)	~28 days from direct sow

Dates are state-wide averages for the dominant zone. Local microclimates — elevation, urban heat, coastal moderation — can shift the window by 1-2 weeks. Use the frost-date calculator for a date tuned to your town.

Why Kentucky's climate shifts the radishes dates

Kentucky's last spring frost averages mid-April and first fall frost mid-October, which sets the whole planting clock. Kentucky has a mild four-season climate with a long, humid summer and a winter that rarely tests hardy perennials. Sow early — radishes bolt once daytime temperatures hold above 24 °C, so the earlier they go in, the longer the harvest.

Radishes are the fastest root crop — spring types mature in 22-30 days from direct sowing, making them ideal row-markers alongside slower crops. Sow 2-4 weeks before the last spring frost as soon as soil can be worked; they bolt and become pithy and peppery hot if left too long in warming soil. Succession-sow every 7-10 days for a continuous harvest; daikon and winter types sown in late summer take 50-70 days and tolerate heavier frost.

Frost-risk note

Don't plant before mid-April — a hard freeze can still set young plants back. In the eastern Appalachian highlands (zone 6a) the safe date runs a week or two later.

Regional variation within Kentucky

the eastern Appalachian highlands (zone 6a) runs roughly 1-2 weeks behind the state average; the Ohio River valley around Louisville (zone 7b) can plant 1-2 weeks earlier.

Louisville — USDA zone 7a
Lexington — USDA zone 6b
Bowling Green — USDA zone 7a
Covington — USDA zone 6b

What else to plant in Kentucky around then

The same early window suits peas, lettuce, spinach, and onion sets.

Quick-grow guide

Sun: Full sun — 6+ hours direct.
Soil temperature for germination: 7-29 °C (45-85 °F).
Spacing: 2-3 inches (5-8 cm) between plants.
Days to harvest: ~28 days from planting out.

Frequently asked questions

When is the best time to plant radishes in Kentucky?

In Kentucky (mostly USDA zone 6b), direct-sow radishes late March (before the last frost, mid-April), and harvest from late April. Radishes are half-hardy — young plants shrug off a light frost but not a hard freeze, so sowing can start a couple of weeks before the last spring frost.

What USDA zone is Kentucky?

Most of Kentucky sits in USDA hardiness zone 6b, with the state spanning roughly 6a-7b from the eastern Appalachian highlands (zone 6a) to the Ohio River valley around Louisville (zone 7b). The last spring frost averages mid-April and the first fall frost mid-October.

Can you grow radishes in Kentucky?

Yes. Kentucky's dominant zone 6b supports radishes — the key is timing. Radishes are half-hardy — young plants shrug off a light frost but not a hard freeze, so sowing can start a couple of weeks before the last spring frost.

Does the planting date change across Kentucky?

the eastern Appalachian highlands (zone 6a) runs roughly 1-2 weeks behind the state average; the Ohio River valley around Louisville (zone 7b) can plant 1-2 weeks earlier.

What else can I plant in Kentucky around the same time?

The same early window suits peas, lettuce, spinach, and onion sets.

Source and methodology

State zone spans from the USDA Plant Hardiness Zone Map (2023); frost-date averages from NOAA Climate Data Online. Hot-state two-season timing cross-checked against the UF/IFAS Florida Gardening Calendar and the University of Arizona Cooperative Extension planting calendar. Curated by the Growli editorial team.