When to Plant Borage in Clay County, MN
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.
Clay County, Minnesota is in USDA Zone 3b. The average last spring frost is May 11 and the first fall frost is September 30, giving you a growing season of approximately 142 days.
At an elevation of 1,220 feet, Clay County receives approximately 35.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 80°F, so choose short-season varieties of Borage to ensure they mature before fall.
Clay County Soil Profile
Soil Type
Silt Loam
Soil pH
5.9-6.9
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 Clay County
How your county's soil matches Borage's growing requirements.
Soil pH
Your soil pH (5.9–6.9) overlaps with Borage's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Clay County is excellent for Borage — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.6%) — Borage will thrive.
How to Plant Borage
Fall planting: Sow 12 weeks before your first frost date for a fall harvest.
Succession Planting Borage
Sow every 5.7 weeks. Last sowing by Aug 01 to harvest before frost.
For a dedicated fall crop, sow by Jul 08.
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
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 | — | 1.4" | 0" | ❄️ Dormant |
| Feb | — | 1.5" | 0" | ❄️ Dormant |
| Mar | — | 2.8" | 0" | ❄️ Dormant |
| Apr | — | 3.9" | 0" | ❄️ Dormant |
| May | 2.2" | 3.8" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 3.8" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 4.3" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 4.2" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 2.8" | 0" | ✅ Rainfall sufficient |
| Oct | — | 2.6" | 0" | ❄️ Dormant |
| Nov | — | 2.2" | 0" | ❄️ Dormant |
| Dec | — | 2.2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Clay 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 — Clay County, MN
Borage Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 30 | Mar 30 – Apr 13 |
| Transplant Outdoors | May 4 | May 4 – May 18 |
| Direct Sow | May 4 | May 4 – May 25 |
| Harvest | June 29 | Jun 29 – Aug 17 |
| Fall Sowing | July 8 | Jul 8 – Jul 22 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors |
| May | Transplant Outdoors Direct Sow |
| June | Harvest |
| July | Fall Sowing Harvest |
| August | Harvest |
| 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 3b
📆 Growing Season
142 days in Clay County
Growing Tips for Borage in Clay County
Direct sow Borage outdoors after May 11 in Clay 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 Clay County, MN?
Clay County is in Zone 3b with an average last frost of May 11. Plan your Borage planting based on this frost date — see the calendar above for exact timing.
What planting zone is Clay County, MN?
Clay County, Minnesota is in USDA Hardiness Zone 3b. The average last spring frost is May 11 and first fall frost is September 30.
Plan Your Garden with Confidence
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