When to Plant Borage in Rock County, WI
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.
Rock County, Wisconsin is in USDA Zone 5a. The average last spring frost is April 26 and the first fall frost is October 13, giving you a growing season of approximately 170 days.
At an elevation of 710 feet, Rock County receives approximately 30.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Borage during the growing season.
Rock County Soil Profile
Soil Type
Silt Loam
Soil pH
6.2-7.1
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 — Rock County, WI
Borage Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 22 | Mar 22 – Apr 5 |
| Transplant Outdoors | April 19 | Apr 19 – May 3 |
| Direct Sow | April 12 | Apr 12 – May 3 |
| Fall Sowing | August 4 | Aug 4 – Aug 18 |
| Harvest | June 14 | Jun 14 – Aug 2 |
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 | 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 5a
Growing Season
170 days
Growing Tips for Rock 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 Rock County, WI?
Rock County is in Zone 5a with an average last frost of April 26. Plan your Borage planting based on this frost date — see the calendar above for exact timing.
What planting zone is Rock County, WI?
Rock County, Wisconsin is in USDA Hardiness Zone 5a. The average last spring frost is April 26 and first fall frost is October 13.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Rock County gardeners in Zone 5a organize planting dates, track what's growing, and never miss a planting window.
Get Your Free Garden Planner →Free download. Plan your entire garden season in minutes.