When to Plant Spinach in Barron County, WI
May in Barron County, Wisconsin — your action list
Your Barron County, Wisconsin garden is entering a new phase. Here's what's on the schedule for May and why each task matters now.
-
Get spinach in the ground
Pinch off the lowest leaves on each seedling before you plant — it reduces water loss while the roots catch up.
-
Plant spinach from seed, right in the garden
These tolerate cool soil, so you're not gambling by sowing now.
Get ahead of June
- Starting indoors: spinach
- First harvests: spinach
Spinach is a nutrient-packed cool-season green that grows quickly in spring and fall. It is rich in iron, vitamins, and antioxidants and excellent raw or cooked.
Barron County, Wisconsin is in USDA Zone 4b. The average last spring frost is May 17 and the first fall frost is September 25, giving you a growing season of approximately 131 days.
At an elevation of 1,256 feet, Barron County receives approximately 40.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Spinach to ensure they mature before fall.
Barron County Soil Profile
Soil Type
Silt Loam
Soil pH
5.8-7
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.
Soil Compatibility in Barron County
How your county's soil matches Spinach's growing requirements.
Soil pH
Your soil pH (5.8–7.0) is more acidic than Spinach prefers (6.5–7.5). Add garden lime to raise pH.
Soil Texture
The silt loam soil in Barron County is excellent for Spinach — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.9%) — Spinach will thrive.
How to Plant Spinach
Fall planting: Sow 12 weeks before your first frost date for a fall harvest.
Succession Planting Spinach
Sow every 4 weeks. Last sowing by Aug 06 to harvest before frost.
For a dedicated fall crop, sow by Jul 03.
Plant Water Budget
Monthly Watering Guide for Spinach
Spinach needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.
| Month | Spinach Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.6" | 0" | ❄️ Dormant |
| Feb | — | 1.6" | 0" | ❄️ Dormant |
| Mar | — | 2.8" | 0" | ❄️ Dormant |
| Apr | — | 4.3" | 0" | ❄️ Dormant |
| May | 3" | 4.6" | 0" | ✅ Rainfall sufficient |
| Jun | 3" | 5.6" | 0" | ✅ Rainfall sufficient |
| Jul | 3" | 3.9" | 0" | ✅ Rainfall sufficient |
| Aug | 3" | 4" | 0" | ✅ Rainfall sufficient |
| Sep | 3" | 3.3" | 0" | ✅ Rainfall sufficient |
| Oct | — | 3" | 0" | ❄️ Dormant |
| Nov | — | 3.2" | 0" | ❄️ Dormant |
| Dec | — | 2.5" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Barron County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Spinach Heat Requirements (GDD)
What are Growing Degree Days (GDD)?
Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.
Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.
Spinach Planting Timeline — Barron County, WI
Spinach Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 5 | Apr 5 – Apr 19 |
| Transplant Outdoors | May 17 | May 17 – May 31 |
| Direct Sow | May 10 | May 10 – May 31 |
| Harvest | June 21 | Jun 21 – Aug 23 |
| Fall Sowing | July 3 | Jul 3 – Jul 17 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | Transplant Outdoors Direct Sow |
| June | Harvest |
| July | Fall Sowing Harvest |
| August | Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
0.7"/week · Natural rainfall sufficient
📅 Days to Maturity
35–50 days
🧪 Soil pH
Needs 6.5–7.5 · Your soil: too_acidic
🗺️ USDA Zone
Zone 4b
📆 Growing Season
131 days in Barron County
Growing Tips for Spinach in Barron County
Direct sow Spinach outdoors after May 17 in Barron County when soil has warmed and frost danger has passed.
Your generous 131.0-day season in Barron County allows multiple plantings of Spinach. Sow every 17.0 days for continuous harvest.
General growing tips
Direct sow as soon as soil can be worked in spring. Plant in partial shade for summer crops to delay bolting. Succession plant every 2 weeks for continuous harvest.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Wind pollinated — isolate 1/2 mile for purity. Easy to let bolt in heat.
Spinach in Other Locations
Frequently Asked Questions
When should I plant Spinach in Barron County, WI?
Barron County is in Zone 4b with an average last frost of May 17. Plan your Spinach planting based on this frost date — see the calendar above for exact timing.
What planting zone is Barron County, WI?
Barron County, Wisconsin is in USDA Hardiness Zone 4b. The average last spring frost is May 17 and first fall frost is September 25.
Your Barron County Garden Planner — Free
A 24-page printable planner built for Barron County (Zone 4b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.