When to Plant Potatoes in Waukesha County, WI
Potatoes are a versatile staple crop that produces tubers underground. They come in hundreds of varieties with varying colors, textures, and maturity dates.
Waukesha County, Wisconsin is in USDA Zone 5a. The average last spring frost is April 27 and the first fall frost is October 12, giving you a growing season of approximately 168 days.
At an elevation of 1,352 feet, Waukesha County receives approximately 37.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Potatoes to ensure they mature before fall.
Waukesha County Soil Profile
Soil Type
Silt Loam
Soil pH
6.1-7.3
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
Potatoes Planting Timeline — Waukesha County, WI
Potatoes Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 2 | Mar 2 – Mar 16 |
| Transplant Outdoors | May 11 | May 11 – May 25 |
| Direct Sow | May 4 | May 4 – May 25 |
| Harvest | July 20 | Jul 20 – Sep 28 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | — |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Moderate — regular watering
Days to Maturity
70–120 days
Soil pH
5 – 6.5
USDA Zone
Zone 5a
Growing Season
168 days
Growing Tips for Waukesha County
Plant seed potatoes (not grocery store potatoes) 4 inches deep in spring. Hill soil around stems as plants grow to prevent greening. Stop watering when plants die back.
Companion Planting
Good Companions
Avoid Planting Near
Level Up Your Garden
Potatoes in Other Locations
Frequently Asked Questions
When should I plant Potatoes in Waukesha County, WI?
Waukesha County is in Zone 5a with an average last frost of April 27. Plan your Potatoes planting based on this frost date — see the calendar above for exact timing.
What planting zone is Waukesha County, WI?
Waukesha County, Wisconsin is in USDA Hardiness Zone 5a. The average last spring frost is April 27 and first fall frost is October 12.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Waukesha County gardeners in Zone 5a organize planting dates, track what's growing, and never miss a planting window.
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