When to Plant Basil in Utah
The king of herbs. Basil and tomatoes are best friends in the garden and in the kitchen.
The Short Answer
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 |
Basil 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
Mountain Regions (Zones 4a, 4b, 5a)
Average last frost: May 25 - Jun 15 · Average first frost: Aug 25 - Sep 15
Southern Utah (Zones 6b, 7a, 7b)
Average last frost: Apr 10 - May 1 · Average first frost: Oct 10 - Nov 1
Growing Basil in Utah
Basil in Utah's Climate
Basil thrives in your warm climate and can produce for 5-6 months or more. In the deep South, basil may survive mild winters in sheltered locations. African Blue basil and Thai basil handle heat better than sweet Genovese. Watch for downy mildew in humid conditions — it's become a significant basil disease in warm, humid climates over the past decade.
Soil Considerations for Utah
Alkaline desert soils. Low organic matter. Saline soils in some areas. Heavy amendment with compost and sulfur needed. Make sure soil has warmed to at least 60°F before planting basil outside.
Utah Climate & Growing Season
Arid climate. Intense sun. Low humidity. Wide temperature swings. Irrigation essential everywhere. Basil cannot tolerate any frost, so wait until all frost danger has passed before transplanting outside. Watch local forecasts carefully in spring.
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 basil — transplant timing shifts by several weeks across the state.
Growing Tips
Pinch off flower buds to keep leaves producing. Harvest from the top down, cutting just above a leaf pair. Succession plant for season-long supply.
Companion Planting
Plant basil alongside these companions for better growth:
Keep basil away from:
The Bottom Line
Last reviewed: March 29, 2026