🍠 Can I Plant Radish in Knoxville, TN?

2026 planting guide for Zone 7a · Last frost ~April 3 · Growing season ~211 days

✅ YES — Good temps, but watch for heat — highs near 88°F

Temperature conditions are suitable for Radish. Highs near 88°F are on the warm side — make sure plants have plenty of water.

Planting window: May 4 – May 18
Good to go — plant now while conditions are right.
Live result based on current forecast for Knoxville, TN · Updates every 6 hours
USDA Zone
7a
Last Spring Frost
~April 3
First Fall Frost
October 31
Growing Season
~211 days
Ideal Temp for Radish
40–65°F
Frost Risk
✅ Tolerant

Growing Radish in Knoxville

Knoxville's Zone 7a location in the Tennessee Valley between the Great Smokies and the Cumberland Plateau provides about 211 frost-free days. The valley climate is warm and humid in summer — productive for tomatoes, peppers, beans, and squash. Spring and fall are especially rewarding, with cool-season crops planted in August delivering excellent harvests through November. The mountain backdrop creates interesting microclimate variation across the area.

In Knoxville (last frost around April 3), radish can go out around February — approximately 6 weeks before the last expected frost, making it an early-season opportunity.

Radish thrives between 40°F and 65°F. It tolerates temperatures as low as 32°F, making it a candidate for early spring planting before the last frost date. Expect 22–30 days from transplant to first harvest. One of the fastest vegetables. Spring or fall.

Frequently Asked Questions

When can I plant radish in Knoxville, TN?

In Knoxville (last frost around April 3), radish can go out around February — approximately 6 weeks before the last expected frost, making it an early-season opportunity.

What is the USDA hardiness zone for Knoxville?

Knoxville, TN is in USDA Plant Hardiness Zone 7a. The last expected spring frost is around April 3, and the first fall frost arrives around October 31. This zone classification helps you understand which perennials survive winter and when annual vegetables can safely go outdoors.

Is it safe to plant radish outside in Knoxville right now?

That depends on the current weather forecast. Radish needs temperatures above 32°F (ideally 40–65°F) to thrive. CanIPlant checks your real 7-day forecast and any active frost alerts to give you a live YES, NO, or WAIT answer — just enter your ZIP code.

Can I grow radish in Knoxville 2026?

Yes — Radish grows well in Knoxville, TN. With a Zone 7a climate and a growing season of ~211 days, Knoxville is well-suited for cool-season crops like radish. As a frost-tolerant crop, radish can even go out a few weeks before the last frost date.

Grow Radish in Other Cities

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