Root Vegetable

When to Plant Radishes in Utah

The fastest vegetable in the garden — some varieties are ready in just 25 days. Perfect for impatient gardeners and kids.

The Short Answer

In Utah, soil conditions are an important factor for radishes. Alkaline desert soils. Low organic matter. Saline soils in some areas. Heavy amendment with compost and sulfur needed. Direct sow 4 weeks before your last frost date. Radishes can also be planted in fall, 6 weeks before your first frost.

Utah Frost Dates

Your planting dates depend on which part of Utah you're in. Here are the frost date ranges by region:

Region Zones Last Frost (Spring) First Frost (Fall)
Wasatch Front (SLC) 6a, 6b, 7a Apr 20 - May 10 Oct 1 - Oct 20
Mountain Regions 4a, 4b, 5a May 25 - Jun 15 Aug 25 - Sep 15
Southern Utah 6b, 7a, 7b Apr 10 - May 1 Oct 10 - Nov 1

Radishes Planting Schedule for Utah

Wasatch Front (SLC) (Zones 6a, 6b, 7a)

Average last frost: Apr 20 - May 10 · Average first frost: Oct 1 - Oct 20

Direct Sow
4 wks before frost
Fall Planting
6 wks before first frost

Mountain Regions (Zones 4a, 4b, 5a)

Average last frost: May 25 - Jun 15 · Average first frost: Aug 25 - Sep 15

Direct Sow
4 wks before frost
Fall Planting
6 wks before first frost

Southern Utah (Zones 6b, 7a, 7b)

Average last frost: Apr 10 - May 1 · Average first frost: Oct 10 - Nov 1

Direct Sow
4 wks before frost
Fall Planting
6 wks before first frost

Growing Radishes in Utah

Radishes in Utah's Climate

Radishes are a cool-season sprint in warm climates — sow from October through February and harvest before spring warmth triggers bolting. Succession plant every 2 weeks during the cool window for multiple harvests. The quick maturity (22-30 days) means you can fit several rounds into even a short cool season.

Soil Considerations for Utah

Alkaline desert soils. Low organic matter. Saline soils in some areas. Heavy amendment with compost and sulfur needed. Loose, well-drained soil is especially important for radishes since the edible portion grows underground. If your soil is heavy clay, consider raised beds.

Utah Climate & Growing Season

Arid climate. Intense sun. Low humidity. Wide temperature swings. Irrigation essential everywhere. Radishes can handle frost well, which is an advantage in Utah's climate. You can push planting dates earlier in spring and extend into fall.

Growing season length varies across Utah: Wasatch Front (SLC) (6a, 6b, 7a) has a last frost around Apr 20 - May 10, while Southern Utah (6b, 7a, 7b) sees frost end around Apr 10 - May 1. This difference matters for radishes — but radishes handle frost well, so the timing difference is less critical.

Growing Tips

Don't let them stay in the ground too long — they get pithy and hot. Succession plant every 2 weeks for continuous harvest.

Companion Planting

Plant radishes alongside these companions for better growth:

Peas Lettuce Carrots Spinach

The Bottom Line

Radishes can be grown successfully across Utah, but your exact planting dates depend on which region you're in. Wasatch Front (SLC) gardeners should plan around a Apr 20 - May 10 last frost, while those in Southern Utah can typically plant earlier. For exact dates based on your zip code, use our free planting date finder.

Related Guides

Radishes Growing Guide National planting guide with all states Utah Planting Calendar All plants for Utah Radishes in Alabama Alabama planting dates Radishes in Alaska Alaska planting dates Radishes in Arizona Arizona planting dates Radishes in Arkansas Arkansas planting dates
Note: All dates are based on NOAA 30-year Climate Normals and represent historical averages, not predictions for any specific year. Always check your local weather forecast before planting frost-sensitive crops. Learn about our data sources.

Last reviewed: March 29, 2026

Ready to Start Planting?

Enter your zip code and pick your plant. We'll tell you exactly when to plant, start seeds, and harvest — based on where you live.

Find Your Planting Dates