When to Plant Mulberries in Polk County, WI
Mulberries are fast-growing, long-lived trees that produce abundant sweet-tart berries over an extended harvest period. The berries resemble elongated blackberries.
Polk County, Wisconsin is in USDA Zone 4a. The average last spring frost is May 12 and the first fall frost is September 29, giving you a growing season of approximately 140 days.
At an elevation of 582 feet, Polk County receives approximately 40 inches of rainfall annually with predominantly silt loam soil. Summer highs average 82°F, so choose short-season varieties of Mulberries to ensure they mature before fall.
Polk County Soil Profile
Soil Type
Silt Loam
Soil pH
6-6.9
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.
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Mulberries Planting Timeline — Polk County, WI
Mulberries Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | June 9 | Jun 9 – Jun 23 |
· 120" apart · Rows 144" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | — |
| June | Transplant Outdoors |
| July | — |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Moderate — regular watering
Days to Maturity
730–1825 days
Soil pH
5.5 – 7
USDA Zone
Zone 4a
Growing Season
140 days
Growing Tips for Polk County
Plant away from driveways and patios as fallen berries stain. Minimal pruning is needed. Harvest by shaking branches over a tarp. Birds love mulberries so plant extra.
Companion Planting
Good Companions
Level Up Your Garden
Mulberries in Other Locations
Frequently Asked Questions
When should I plant Mulberries in Polk County, WI?
Polk County is in Zone 4a with an average last frost of May 12. Plan your Mulberries planting based on this frost date — see the calendar above for exact timing.
What planting zone is Polk County, WI?
Polk County, Wisconsin is in USDA Hardiness Zone 4a. The average last spring frost is May 12 and first fall frost is September 29.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Polk County gardeners in Zone 4a 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.