When to Plant Basil in Rio Blanco County, CO
Basil is a fragrant warm-season herb essential to Italian and Thai cuisines. It comes in many varieties including sweet, Thai, purple, and lemon types.
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 Basil during the growing season. With low rainfall, drip irrigation is essential for growing Basil 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
Basil Planting Timeline — Rio Blanco County, CO
Basil Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 14 | Apr 14 – Apr 28 |
| Transplant Outdoors | June 16 | Jun 16 – Jun 30 |
| Direct Sow | June 9 | Jun 9 – Jun 30 |
| Harvest | August 11 | Aug 11 – Oct 13 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | — |
| June | Transplant Outdoors Direct Sow |
| July | — |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Moderate — regular watering
Days to Maturity
50–75 days
Soil pH
6 – 7
USDA Zone
Zone 5a
Growing Season
107 days
Growing Tips for Rio Blanco County
Start seeds indoors or direct sow after last frost. Pinch flower buds to extend leaf production. Harvest leaves from the top down, cutting just above a leaf pair.
Companion Planting
Good Companions
Avoid Planting Near
Level Up Your Garden
Isolate 150 ft between varieties. Different basil species can cross.
Basil in Other Locations
Frequently Asked Questions
When should I plant Basil in Rio Blanco County, CO?
Rio Blanco County is in Zone 5a with an average last frost of June 2. Plan your Basil 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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