When to Plant Peppers in St. Louis County, MN
St. Louis County, Minnesota gardeners: here's your May plan
We've pulled the most time-sensitive tasks for St. Louis County, Minnesota this May and put them front and centre. Tackle them in order.
Before June arrives, get these ready
- Transplants going out: peppers
- Direct-sowing: peppers
Sweet peppers are warm-season crops producing fruits in a rainbow of colors. They turn from green to red, yellow, or orange as they ripen, increasing in sweetness.
St. Louis County, Minnesota is in USDA Zone 3b. The average last spring frost is June 2 and the first fall frost is September 10, giving you a growing season of approximately 100 days.
At an elevation of 531 feet, St. Louis County receives approximately 36.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 78°F, so choose short-season varieties of Peppers to ensure they mature before fall.
St. Louis County Soil Profile
Soil Type
Silt Loam
Soil pH
6-7
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 St. Louis County
How your county's soil matches Peppers's growing requirements.
Soil pH
Your soil pH (6.0–7.0) is within Peppers's preferred range (6.0–7.0).
Soil Texture
The silt loam soil in St. Louis County is excellent for Peppers — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Peppers.
Organic Matter
Organic matter is excellent (4.0%) — Peppers will thrive.
How to Plant Peppers
How Much Peppers to Grow
For a family of 4, plant approximately 12 peppers plants in about 30 sq ft. In St. Louis County's 100-day season, you'll have plenty of time for a full harvest. Plan your garden layout →
Plant Water Budget
Monthly Watering Guide for Peppers
Peppers needs approximately 1.1 inches of water per week (4.8" per month). Here's how your county's rainfall compares month by month.
| Month | Peppers Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.6" | 0" | ❄️ Dormant |
| Feb | — | 1.7" | 0" | ❄️ Dormant |
| Mar | — | 2.7" | 0" | ❄️ Dormant |
| Apr | — | 3.2" | 0" | ❄️ Dormant |
| May | — | 3.9" | 0" | ❄️ Dormant |
| Jun | 4.8" | 5.1" | 0" | ✅ Rainfall sufficient |
| Jul | 4.8" | 4.4" | 0.4" | 💧 Light watering |
| Aug | 4.8" | 3.7" | 1.1" | 💧 Light watering |
| Sep | 4.8" | 3.1" | 1.7" | 💧 Light watering |
| Oct | — | 2.8" | 0" | ❄️ Dormant |
| Nov | — | 2.3" | 0" | ❄️ Dormant |
| Dec | — | 1.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Jun–Sep in St. Louis County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Peppers 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.
Peppers Planting Timeline — St. Louis County, MN
Peppers Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 17 | Mar 17 – Mar 31 |
| Transplant Outdoors | June 23 | Jun 23 – Jul 7 |
| Direct Sow | June 16 | Jun 16 – Jul 7 |
| Harvest | August 25 | Aug 25 – Oct 27 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | — |
| May | — |
| June | Transplant Outdoors Direct Sow |
| July | Transplant Outdoors Direct Sow |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1.1"/week · Natural rainfall sufficient
📅 Days to Maturity
60–90 days
🧪 Soil pH
Needs 6–7 · Your soil: ideal
🗺️ USDA Zone
Zone 3b
📆 Growing Season
100 days in St. Louis County
Growing Tips for Peppers in St. Louis County
Direct sow Peppers outdoors after June 02 in St. Louis County when soil has warmed and frost danger has passed.
Your 100.0-day growing season in St. Louis County is tight for Peppers (60.0-90.0 days to maturity). Start indoors and choose early-maturing varieties.
Common pests for Peppers in this region include tomato hornworm and aphids. Use row covers early in the season and inspect plants weekly.
General growing tips
Start seeds indoors 8-10 weeks before last frost. Transplant when nighttime temperatures stay above 55F. Avoid high-nitrogen fertilizers which promote leaves over fruit.
Recommended Peppers Varieties for St. Louis County
Fast-maturing pepper varieties for shorter seasons
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Isolate 300 ft for purity. Hot and sweet peppers can cross-pollinate.
Peppers in Other Locations
Frequently Asked Questions
When should I plant Peppers in St. Louis County, MN?
St. Louis County is in Zone 3b with an average last frost of June 2. Plan your Peppers planting based on this frost date — see the calendar above for exact timing.
What planting zone is St. Louis County, MN?
St. Louis County, Minnesota is in USDA Hardiness Zone 3b. The average last spring frost is June 2 and first fall frost is September 10.
Your St. Louis County Garden Planner — Free
A 24-page printable planner built for St. Louis County (Zone 3b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.