When to plant Borage in Cass County, IA
Spring Borage in Cass County goes in April 11–May 2, once nighttime temps stop dipping near freezing. A second sowing from July 31 to August 14 extends the harvest into fall.
When to Plant Borage in Cass County, IA
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, Iowa is in USDA Zone 5b. The average last spring frost is April 25 and the first fall frost is October 9, giving you a growing season of approximately 167 days.
At an elevation of 1,043 feet, Cass County receives approximately 31.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Borage during the growing season.
Cass County Soil Profile
Soil Type
Silt Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Borage Planting Timeline — Cass County, IA
Borage Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 21 | Mar 21 – Apr 4 |
| Transplant Outdoors | April 18 | Apr 18 – May 2 |
| Direct Sow | April 11 | Apr 11 – May 2 |
| Harvest | June 13 | Jun 13 – Aug 1 |
| Fall Sowing | July 31 | Jul 31 – Aug 14 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | Harvest |
| 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
Needs 6–7 · Your soil: N/A
🗺️ USDA Zone
Zone 5b
📆 Growing Season
167 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, IA?
Cass County is in Zone 5b with an average last frost of April 25. Plan your Borage planting based on this frost date — see the calendar above for exact timing.
What planting zone is Cass County, IA?
Cass County, Iowa is in USDA Hardiness Zone 5b. The average last spring frost is April 25 and first fall frost is October 9.
When should I plant Borage in Cass County, IA?
In Cass County, IA, plant Borage after the last frost (around April 25) and before the first frost (around October 9). Best results when soil holds above 50°F.
What growing zone is Cass County, IA for Borage?
Cass County sits in USDA Zone 5b. 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 167-day frost-free season, with last frost around April 25 and first frost around October 9.
Your Cass County Garden Planner — Free
A 22-page printable planner built for Cass County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.