When to Plant Squash (Summer) in Utah
Zucchini and yellow squash are the garden's most generous producers. You'll be sharing with neighbors by midsummer.
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 |
Squash (Summer) 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 Squash (Summer) in Utah
Squash (Summer) in Utah's Climate
Your long season supports both summer and winter squash without the season-length anxiety that northern growers face. Spring and fall plantings are both productive. Squash vine borer typically has two generations in warm climates — stagger plantings to ensure some production survives.
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 squash (summer) outside.
Utah Climate & Growing Season
Arid climate. Intense sun. Low humidity. Wide temperature swings. Irrigation essential everywhere. Squash (Summer) 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 squash (summer) — transplant timing shifts by several weeks across the state.
Growing Tips
Harvest when fruits are 6-8 inches long for best flavor. Larger squash become seedy and tough.
Companion Planting
Plant squash (summer) alongside these companions for better growth:
Keep squash (summer) away from:
The Bottom Line
Last reviewed: March 29, 2026