Blog

When to Plant Mustard Greens in Red Lake County, MN

Red Lake County, Minnesota Zone 3b May

May in Red Lake County, Minnesota — your action list

May is a pivotal month for Red Lake County, Minnesota gardens. Focus on these tasks first and you'll set up the rest of the season for success.

Avg. last frost May 11
Avg. first frost October 1
Soil temp (4") 48°F
Watering Moderate
Pest pressure Low
Daylight 14.9 hrs
  1. Set out mustard greens seedlings

    Harden off for 7 days — a little more sun each day — before planting. That's the difference between a seedling that thrives and one that stalls.

  2. Put mustard greens seeds straight in the ground

    Thin ruthlessly once seedlings are up. Crowded roots mean smaller crops from every plant.

June prep starts now
  • Starting indoors: mustard greens
  • First harvests: mustard greens

Instant PDF download. No spam, unsubscribe any time.

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.

Red Lake County, Minnesota is in USDA Zone 3b. The average last spring frost is May 11 and the first fall frost is October 1, giving you a growing season of approximately 143 days.

At an elevation of 616 feet, Red Lake County receives approximately 36.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 80°F, so choose short-season varieties of Mustard Greens to ensure they mature before fall.

Red Lake County, MN (Zone 3b) Short season
143 days
Last Spring Frost May 11
143 growing days
First Fall Frost October 1
Share this guide:

Red Lake County Soil Profile

Soil Type

Silt Loam

Soil pH

6.1-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (50 days to spare)
Start indoors: Mar 21 Transplant: May 2 🍅 Harvest: Jun 6 – Aug 8
Recommended (50%) ✓ Fits season (45 days to spare)
Start indoors: Mar 30 Transplant: May 11 🍅 Harvest: Jun 15 – Aug 17
Safe Start (90%) ✓ Fits season (47 days to spare)
Start indoors: Apr 10 Transplant: May 22 🍅 Harvest: Jun 26 – Aug 28

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 Red Lake County

How your county's soil matches Mustard Greens's growing requirements.

Soil pH

Your soil pH (6.1–6.8) is within Mustard Greens's preferred range (6.0–7.0).

Soil Texture

The silt loam soil in Red Lake County is excellent for Mustard Greens — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (4.0%). Annual compost additions will help Mustard Greens.

How to Plant Mustard Greens

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

Fall planting: Sow 12 weeks before your first frost date for a fall harvest.

Succession Planting Mustard Greens

5
successive plantings in your 143-day season

Sow every 3.4 weeks. Last sowing by Aug 12 to harvest before frost.

For a dedicated fall crop, sow by Jul 09.

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
1.1″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

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 1.6" 0" ❄️ Dormant
Mar 2.8" 0" ❄️ Dormant
Apr 3.9" 0" ❄️ Dormant
May 3" 3.6" 0" ✅ Rainfall sufficient
Jun 3" 4" 0" ✅ Rainfall sufficient
Jul 3" 4.4" 0" ✅ Rainfall sufficient
Aug 3" 4.3" 0" ✅ Rainfall sufficient
Sep 3" 3" 0" ✅ Rainfall sufficient
Oct 3" 2.8" 0.2" 💧 Light watering
Nov 2.8" 0" ❄️ Dormant
Dec 2.1" 0" ❄️ Dormant

Water needs are for active growing months only (May–Oct in Red Lake 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 needs ~400 GDD — county provides 1,430 GDD Excellent fit

Mustard Greens Planting Timeline — Red Lake County, MN

Mustard Greens Planting Calendar

Activity When Date Range
Start Indoors March 30 Mar 30 – Apr 13
Transplant Outdoors May 11 May 11 – May 25
Direct Sow May 4 May 4 – May 25
Harvest June 15 Jun 15 – Aug 17
Fall Sowing July 9 Jul 9 – Jul 23

Plant 0.5" deep · 6" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Start Indoors
May Transplant Outdoors Direct Sow
June Harvest
July Fall Sowing Harvest
August Harvest
September
October
November
December
Share this guide:

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

143 days in Red Lake County

Growing Tips for Mustard Greens in Red Lake County

Direct sow Mustard Greens outdoors after May 11 in Red Lake County when soil has warmed and frost danger has passed.

Your generous 143.0-day season in Red Lake County allows multiple plantings of Mustard Greens. Sow every 15.0 days for continuous harvest.

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

  • Strawberries

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Mustard Greens in Red Lake County, MN?

Red Lake County is in Zone 3b with an average last frost of May 11. Plan your Mustard Greens planting based on this frost date — see the calendar above for exact timing.

What planting zone is Red Lake County, MN?

Red Lake County, Minnesota is in USDA Hardiness Zone 3b. The average last spring frost is May 11 and first fall frost is October 1.

🌱

Your Red Lake County Garden Planner — Free

A 24-page printable planner built for Red Lake 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.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Red Lake County, MN. Local conditions may vary. Last updated: May 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.