When to plant Borage in Cass County, MN
Cass County sits in USDA Zone 4a. Plant Borage between May 5 (after last frost on May 12) and May 26. A second sowing from July 6 to July 20 extends the harvest into fall.
When to Plant Borage in Cass 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.
Cass County, Minnesota is in USDA Zone 4a. The average last spring frost is May 12 and the first fall frost is September 28, giving you a growing season of approximately 139 days.
At an elevation of 938 feet, Cass County receives approximately 32.4 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.
Cass County Soil Profile
Soil Type
Silt Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Borage Planting Timeline — Cass County, MN
Borage Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 31 | Mar 31 – Apr 14 |
| Transplant Outdoors | May 5 | May 5 – May 19 |
| Direct Sow | May 5 | May 5 – May 26 |
| Harvest | June 30 | Jun 30 – Aug 18 |
| Fall Sowing | July 6 | Jul 6 – Jul 20 |
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
Low — drought tolerant
📅 Days to Maturity
50–60 days
🧪 Soil pH
Needs 6–7 · Your soil: N/A
🗺️ USDA Zone
Zone 4a
📆 Growing Season
139 days in Cass County
Growing Tips for Cass 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
Check more plant combinations with our Companion Planting Checker →
Borage in Other Locations
Frequently Asked Questions
When should I plant Borage in Cass County, MN?
Cass County is in Zone 4a with an average last frost of May 12. Plan your Borage planting based on this frost date — see the calendar above for exact timing.
What planting zone is Cass County, MN?
Cass County, Minnesota is in USDA Hardiness Zone 4a. The average last spring frost is May 12 and first fall frost is September 28.
When should I plant Borage in Cass County, MN?
In Cass County, MN, plant Borage after the last frost (around May 12) and before the first frost (around September 28). Best results when soil holds above 50°F.
What growing zone is Cass County, MN for Borage?
Cass County sits in USDA Zone 4a. Borage grows reliably in zones 3a through 11b, so it's a good fit here.
Can Borage grow in Cass County's climate?
Yes — Borage grows well in Cass County's temperate climate. Cass County averages a 139-day frost-free season, with last frost around May 12 and first frost around September 28.
Your Cass County Garden Planner — Free
A 22-page printable planner built for Cass County (Zone 4a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.