When to Plant Cumin in Rio Blanco County, CO
Cumin is a warm-season annual herb whose seeds are one of the most widely used spices globally. It requires a long, hot growing season of 3-4 months.
Rio Blanco County, Colorado is in USDA Zone 5a. The average last spring frost is June 2 and the first fall frost is September 17, giving you a growing season of approximately 107 days.
At an elevation of 6,974 feet, Rio Blanco County receives approximately 19 inches of rainfall annually with predominantly loam soil. Summer highs average 86°F, providing good warmth for Cumin during the growing season. With low rainfall, drip irrigation is essential for growing Cumin successfully. Mulch heavily to conserve soil moisture.
Rio Blanco County Soil Profile
Soil Type
Loam
Soil pH
6.4-7.7
Drainage
Well Drained
Plant Planting Risk Windows
Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.
Plant Water Budget
Water stress score is 8/10 — consider drought-tolerant varieties and mulching
Cumin Planting Timeline — Rio Blanco County, CO
Cumin Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 28 | Apr 28 – May 12 |
| Transplant Outdoors | May 26 | May 26 – Jun 9 |
| Direct Sow | May 19 | May 19 – Jun 9 |
| Fall Sowing | July 9 | Jul 9 – Jul 23 |
| Harvest | September 8 | Sep 8 – Nov 10 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | Start Indoors Transplant Outdoors Direct Sow |
| June | Transplant Outdoors Direct Sow |
| July | Fall Sowing |
| August | — |
| September | Harvest |
| October | Harvest |
| November | Harvest |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Low — drought tolerant
Days to Maturity
100–120 days
Soil pH
6 – 8
USDA Zone
Zone 5a
Growing Season
107 days
Growing Tips for Rio Blanco County
Start seeds indoors 4 weeks before last frost. Transplant after all danger of frost. Harvest when seed heads turn brown. Requires consistent warmth for proper seed development.
Companion Planting
Good Companions
Avoid Planting Near
Level Up Your Garden
Cumin in Other Locations
Frequently Asked Questions
When should I plant Cumin in Rio Blanco County, CO?
Rio Blanco County is in Zone 5a with an average last frost of June 2. Plan your Cumin planting based on this frost date — see the calendar above for exact timing.
What planting zone is Rio Blanco County, CO?
Rio Blanco County, Colorado is in USDA Hardiness Zone 5a. The average last spring frost is June 2 and first fall frost is September 17.
Plan Your Garden with Confidence
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