When to Plant Borage in Carter County, TN
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.
Carter County, Tennessee is in USDA Zone 6b. The average last spring frost is April 16 and the first fall frost is October 22, giving you a growing season of approximately 189 days.
At an elevation of 3,776 feet, Carter County receives approximately 53.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91°F, providing good warmth for Borage during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Borage root diseases.
Carter County Soil Profile
Soil Type
Silt Loam
Soil pH
5.6-7
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.
Soil Compatibility in Carter County
How your county's soil matches Borage's growing requirements.
Soil pH
Your soil pH (5.6–7.0) overlaps with Borage's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Carter County is excellent for Borage — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Borage prefers dry conditions but your soil drains poorly. Use raised beds or mounded rows to prevent root rot.
Organic Matter
Organic matter is moderate (2.8%). Annual compost additions will help Borage.
How to Plant Borage
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Borage
Sow every 5.7 weeks. Last sowing by Aug 23 to harvest before frost.
For a dedicated fall crop, sow by Aug 13.
Plant Water Budget
Monthly Watering Guide for Borage
Borage needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.
| Month | Borage Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 4.8" | 0" | ❄️ Dormant |
| Feb | — | 4" | 0" | ❄️ Dormant |
| Mar | — | 5.2" | 0" | ❄️ Dormant |
| Apr | 2.2" | 4.5" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 4.5" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 4.5" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 5.1" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 5.6" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 4.6" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 3.2" | 0" | ✅ Rainfall sufficient |
| Nov | — | 3.7" | 0" | ❄️ Dormant |
| Dec | — | 4.2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Carter County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Borage Heat Requirements (GDD)
What are Growing Degree Days (GDD)?
Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.
Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.
Borage Planting Timeline — Carter County, TN
Borage Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 12 | Mar 12 – Mar 26 |
| Transplant Outdoors | April 9 | Apr 9 – Apr 23 |
| Direct Sow | April 2 | Apr 2 – Apr 23 |
| Harvest | June 4 | Jun 4 – Jul 23 |
| Fall Sowing | August 13 | Aug 13 – Aug 27 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | — |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
50–60 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 6b
📆 Growing Season
189 days in Carter County
Growing Tips for Borage in Carter County
Direct sow Borage outdoors after April 16 in Carter County when soil has warmed and frost danger has passed.
General growing tips
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
Check more plant combinations with our Companion Planting Checker →
Borage in Other Locations
Frequently Asked Questions
When should I plant Borage in Carter County, TN?
Carter County is in Zone 6b with an average last frost of April 16. Plan your Borage planting based on this frost date — see the calendar above for exact timing.
What planting zone is Carter County, TN?
Carter County, Tennessee is in USDA Hardiness Zone 6b. The average last spring frost is April 16 and first fall frost is October 22.
Plan Your Garden with Confidence
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