When to plant Mustard Greens in St. Louis County County,
In St. Louis County County, plant Mustard Greens in spring between May 26 and June 16, once soil temps hold above 50°F. St. Louis County County's last frost averages June 2, so be cautious and check the 10-day forecast before planting tender crops. For a fall crop, sow between June 18 and July 2 — roughly 50 days before the first frost on September 10.
When to Plant Mustard Greens in St. Louis County, MN
June in the garden — St. Louis County, Minnesota
Each item below is timed to St. Louis County, Minnesota's frost dates and soil temperatures. Skip nothing, stress about nothing.
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Harden off and plant mustard greens
Plant tomatoes deep — bury the stem up to the first true leaves to grow extra roots. Everything else goes in at the same depth it grew in the tray.
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Plant your fall garden: mustard greens
Count back from your first frost (September 10) — these need to mature before the cold arrives.
To set up a strong July, finish these tasks
- Starting indoors: mustard greens
- First harvests: mustard greens
Mustard greens are fast-growing brassicas with a spicy, peppery kick. They come in green, red, and purple varieties and are excellent cooked or in salads.
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 Mustard Greens to ensure they mature before fall.
St. Louis County Soil Profile
Soil Type
Silt Loam
Soil pH
6-7
Drainage
Well Drained
Mustard Greens 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 Mustard Greens's growing requirements.
Soil pH
Your soil pH (6.0–7.0) is within Mustard Greens's preferred range (6.0–7.0).
Soil Texture
The silt loam soil in St. Louis County is excellent for Mustard Greens — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Mustard Greens.
Organic Matter
Organic matter is excellent (4.0%) — Mustard Greens will thrive.
How to Plant Mustard Greens
Fall planting: Sow 12 weeks before your first frost date for a fall harvest.
Succession Planting Mustard Greens
Sow every 3.4 weeks. Last sowing by Jul 22 to harvest before frost.
For a dedicated fall crop, sow by Jun 18.
Mustard Greens Water Budget
Monthly Watering Guide for Mustard Greens
Mustard Greens needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.
| Month | Mustard Greens 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 | 3" | 5.1" | 0" | ✅ Rainfall sufficient |
| Jul | 3" | 4.4" | 0" | ✅ Rainfall sufficient |
| Aug | 3" | 3.7" | 0" | ✅ Rainfall sufficient |
| Sep | 3" | 3.1" | 0" | ✅ Rainfall sufficient |
| 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.
Mustard Greens 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.
Mustard Greens Planting Timeline — St. Louis County, MN
Mustard Greens Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 21 | Apr 21 – May 5 |
| Transplant Outdoors | June 2 | Jun 2 – Jun 16 |
| Direct Sow | May 26 | May 26 – Jun 16 |
| Harvest | July 7 | Jul 7 – Sep 8 |
| Fall Sowing | June 18 | Jun 18 – Jul 2 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | Start Indoors Direct Sow |
| June | Transplant Outdoors Direct Sow Fall Sowing |
| July | Fall Sowing Harvest |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
0.7"/week · Natural rainfall sufficient
📅 Days to Maturity
30–50 days
🧪 Soil pH
Needs 6–7 · Your soil: ideal
🗺️ USDA Zone
Zone 3b
📆 Growing Season
100 days in St. Louis County
Growing Tips for Mustard Greens in St. Louis County
Direct sow Mustard Greens outdoors after June 02 in St. Louis County when soil has warmed and frost danger has passed.
Common pests for Mustard Greens in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.
General growing tips
Direct sow in early spring or fall. Harvest young leaves for milder flavor. Plants bolt quickly in heat so grow as a cool-season crop or provide shade.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Mustard Greens in Other Locations
Frequently Asked Questions
When should I plant Mustard Greens in St. Louis County, MN?
St. Louis County is in Zone 3b with an average last frost of June 2. Plan your Mustard Greens 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.
When should I plant Mustard Greens in St. Louis County County, ?
In St. Louis County County, , plant Mustard Greens after the last frost (around June 2) and before the first frost (around September 10). Best results when soil holds above 50°F.
What growing zone is St. Louis County County, for Mustard Greens?
St. Louis County County sits in USDA Zone 3b. Mustard Greens grows reliably in zones 2a through 11b, so it's a good fit here.
Can Mustard Greens grow in St. Louis County County's climate?
Yes — Mustard Greens grows well in St. Louis County County's temperate climate. St. Louis County County averages a 100-day frost-free season, with last frost around June 2 and first frost around September 10.
Your St. Louis County Garden Planner — Free
A 22-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.