When to Plant Brussels Sprouts in Trempealeau County, WI
This month in Trempealeau County, Wisconsin
Your Trempealeau County, Wisconsin garden is entering a new phase. Here's what's on the schedule for May and why each task matters now.
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Set out brussels sprouts seedlings
Frost risk is low now in Trempealeau County, Wisconsin. If you've been covering beds overnight, you can stop.
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Sow brussels sprouts where they'll grow
Rake a smooth bed, make a shallow furrow, drop seeds at the spacing on the packet, water gently, walk away.
To set up a strong June, finish these tasks
- Starting indoors: brussels sprouts
Brussels sprouts are a cold-hardy brassica that produces miniature cabbage-like heads along a tall stalk. Flavor improves after a light frost.
Trempealeau County, Wisconsin is in USDA Zone 4b. The average last spring frost is May 15 and the first fall frost is September 30, giving you a growing season of approximately 138 days.
At an elevation of 1,222 feet, Trempealeau County receives approximately 39.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 81°F, so choose short-season varieties of Brussels Sprouts to ensure they mature before fall.
Trempealeau County Soil Profile
Soil Type
Silt Loam
Soil pH
5.7-7.2
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 Trempealeau County
How your county's soil matches Brussels Sprouts's growing requirements.
Soil pH
Your soil pH (5.7–7.2) overlaps with Brussels Sprouts's range (6.0–7.5), though not a perfect match.
Soil Texture
The silt loam soil in Trempealeau County is excellent for Brussels Sprouts — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.4%) — Brussels Sprouts will thrive.
How to Plant Brussels Sprouts
Fall planting: Sow 12 weeks before your first frost date for a fall harvest.
Plant Water Budget
Monthly Watering Guide for Brussels Sprouts
Brussels Sprouts needs approximately 0.9 inches of water per week (3.9" per month). Here's how your county's rainfall compares month by month.
| Month | Brussels Sprouts Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.6" | 0" | ❄️ Dormant |
| Feb | — | 1.8" | 0" | ❄️ Dormant |
| Mar | — | 2.7" | 0" | ❄️ Dormant |
| Apr | — | 4.1" | 0" | ❄️ Dormant |
| May | 3.9" | 4.4" | 0" | ✅ Rainfall sufficient |
| Jun | 3.9" | 4.9" | 0" | ✅ Rainfall sufficient |
| Jul | 3.9" | 4.2" | 0" | ✅ Rainfall sufficient |
| Aug | 3.9" | 4.1" | 0" | ✅ Rainfall sufficient |
| Sep | 3.9" | 3.5" | 0.4" | 💧 Light watering |
| Oct | — | 3.6" | 0" | ❄️ Dormant |
| Nov | — | 2.7" | 0" | ❄️ Dormant |
| Dec | — | 2.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Trempealeau County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Brussels Sprouts 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.
Brussels Sprouts Planting Timeline — Trempealeau County, WI
Brussels Sprouts Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 3 | Apr 3 – Apr 17 |
| Transplant Outdoors | May 15 | May 15 – May 29 |
| Direct Sow | May 8 | May 8 – May 29 |
| Harvest | August 14 | Aug 14 – Oct 9 |
| Fall Sowing | July 8 | Jul 8 – Jul 22 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Fall Sowing |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.9"/week · Natural rainfall sufficient
📅 Days to Maturity
90–130 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 4b
📆 Growing Season
138 days in Trempealeau County
Growing Tips for Brussels Sprouts in Trempealeau County
Direct sow Brussels Sprouts outdoors after May 15 in Trempealeau County when soil has warmed and frost danger has passed.
Your 138.0-day growing season in Trempealeau County is tight for Brussels Sprouts (90.0-130.0 days to maturity). Start indoors and choose early-maturing varieties.
Common pests for Brussels Sprouts in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.
General growing tips
Start seeds indoors 12-14 weeks before first fall frost. Stake tall plants to prevent toppling. Remove lower leaves as sprouts develop to improve air circulation.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Brussels Sprouts in Other Locations
Frequently Asked Questions
When should I plant Brussels Sprouts in Trempealeau County, WI?
Trempealeau County is in Zone 4b with an average last frost of May 15. Plan your Brussels Sprouts planting based on this frost date — see the calendar above for exact timing.
What planting zone is Trempealeau County, WI?
Trempealeau County, Wisconsin is in USDA Hardiness Zone 4b. The average last spring frost is May 15 and first fall frost is September 30.
Your Trempealeau County Garden Planner — Free
A 24-page printable planner built for Trempealeau 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.