When to Plant Parsley in Wyoming
More than a garnish. Parsley is a biennial that produces abundantly its first year and is one of the most nutritious herbs.
The Short Answer
Wyoming Frost Dates
Your planting dates depend on which part of Wyoming you're in. Here are the frost date ranges by region:
| Region | Zones | Last Frost (Spring) | First Frost (Fall) |
|---|---|---|---|
| Eastern Wyoming | 4a, 4b, 5a | May 10 - May 30 | Sep 10 - Sep 25 |
| Western Wyoming | 3a, 3b, 4a | May 25 - Jun 15 | Aug 25 - Sep 15 |
| Southern Wyoming | 4b, 5a, 5b | May 15 - Jun 1 | Sep 5 - Sep 20 |
Parsley Planting Schedule for Wyoming
Eastern Wyoming (Zones 4a, 4b, 5a)
Average last frost: May 10 - May 30 · Average first frost: Sep 10 - Sep 25
Western Wyoming (Zones 3a, 3b, 4a)
Average last frost: May 25 - Jun 15 · Average first frost: Aug 25 - Sep 15
Southern Wyoming (Zones 4b, 5a, 5b)
Average last frost: May 15 - Jun 1 · Average first frost: Sep 5 - Sep 20
Growing Parsley in Wyoming
Parsley in Wyoming's Climate
Parsley is one of your most reliable herbs — the biennial handles frost, grows through your moderate summers, and keeps producing from May through November. Start seeds indoors in February (parsley germinates notoriously slowly — 14-28 days). The plant is biennial: lush leaves year one, flowers and seeds year two.
Soil Considerations for Wyoming
Alkaline, thin soils. Dry climate means little organic matter naturally. Wind erosion a significant challenge. Heavy amendment needed.
Wyoming Climate & Growing Season
Short growing season. Very windy — wind protection essential for gardens. Low humidity. Cool nights even in summer at elevation.
Growing season length varies across Wyoming: Eastern Wyoming (4a, 4b, 5a) has a last frost around May 10 - May 30, while Southern Wyoming (4b, 5a, 5b) sees frost end around May 15 - Jun 1. This difference matters for parsley — adjust your planting dates to match your specific region.
Growing Tips
Parsley seeds are notoriously slow to germinate — soak overnight before planting. It's a biennial: lush leaves year one, seeds year two.
Companion Planting
Plant parsley alongside these companions for better growth:
The Bottom Line
Last reviewed: March 29, 2026