When to Plant Borage in Broomfield County, CO
Borage is a self-seeding annual herb with star-shaped blue flowers that attract pollinators. Its leaves have a cucumber-like flavor and the flowers are edible.
Broomfield County, Colorado is in USDA Zone 5b. The average last spring frost is May 14 and the first fall frost is September 26, giving you a growing season of approximately 135 days.
At an elevation of 7,037 feet, Broomfield County receives approximately 13.9 inches of rainfall annually with predominantly loam soil. Summer highs average 87°F, providing good warmth for Borage during the growing season. With low rainfall, drip irrigation is essential for growing Borage successfully. Mulch heavily to conserve soil moisture.
Broomfield County Soil Profile
Soil Type
Loam
Soil pH
6.2-8.2
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 6/10 — consider drought-tolerant varieties and mulching
Borage Planting Timeline — Broomfield County, CO
Borage Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 9 | Apr 9 – Apr 23 |
| Transplant Outdoors | May 7 | May 7 – May 21 |
| Direct Sow | April 30 | Apr 30 – May 21 |
| Fall Sowing | July 18 | Jul 18 – Aug 1 |
| Harvest | July 2 | Jul 2 – Aug 20 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Fall Sowing Harvest |
| August | Fall Sowing Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Low — drought tolerant
Days to Maturity
50–60 days
Soil pH
6 – 7
USDA Zone
Zone 5b
Growing Season
135 days
Growing Tips for Broomfield County
Direct sow in spring as borage does not transplant well. Allow some plants to go to seed for next year. Young leaves are best; older leaves become bristly.
Companion Planting
Good Companions
Level Up Your Garden
Borage in Other Locations
Frequently Asked Questions
When should I plant Borage in Broomfield County, CO?
Broomfield County is in Zone 5b with an average last frost of May 14. Plan your Borage planting based on this frost date — see the calendar above for exact timing.
What planting zone is Broomfield County, CO?
Broomfield County, Colorado is in USDA Hardiness Zone 5b. The average last spring frost is May 14 and first fall frost is September 26.
Plan Your Garden with Confidence
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