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When to Plant Mustard Greens in Scott County, IL

Scott County, Illinois Zone 6a May

May to-do list for Scott County, Illinois

We've pulled the most time-sensitive tasks for Scott County, Illinois this May and put them front and centre. Tackle them in order.

Avg. last frost April 14
Avg. first frost October 17
Soil temp (4") 60°F
Watering Low
Pest pressure Low
Daylight 14.2 hrs
  1. Begin indoor sowing: mustard greens

    You're about 23 weeks out from your last frost — the perfect window to get these germinating indoors.

  2. It's harvest week for mustard greens

    Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.

June prep starts now
  • First harvests: mustard greens

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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.

Scott County, Illinois is in USDA Zone 6a. The average last spring frost is April 14 and the first fall frost is October 17, giving you a growing season of approximately 186 days.

At an elevation of 987 feet, Scott County receives approximately 37.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Mustard Greens to ensure they mature before fall.

Scott County, IL (Zone 6a) Moderate season
186 days
Last Spring Frost April 14
186 growing days
First Fall Frost October 17

Scott County Soil Profile

Soil Type

Silt Loam

Soil pH

6-7.1

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (87 days to spare)
Start indoors: Mar 5 Transplant: Apr 9 🍅 Harvest: May 14 – Jul 16
Recommended (50%) ✓ Fits season (88 days to spare)
Start indoors: Mar 10 Transplant: Apr 14 🍅 Harvest: May 19 – Jul 21
Safe Start (90%) ✓ Fits season (82 days to spare)
Start indoors: Mar 27 Transplant: May 1 🍅 Harvest: Jun 5 – Aug 7

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 Scott County

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

Soil pH

Your soil pH (6.0–7.1) overlaps with Mustard Greens's range (6.0–7.0), though not a perfect match.

Soil Texture

The silt loam soil in Scott 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 (4.4%) — Mustard Greens will thrive.

How to Plant Mustard Greens

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

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Mustard Greens

7
successive plantings in your 186-day season

Sow every 3.4 weeks. Last sowing by Aug 28 to harvest before frost.

For a dedicated fall crop, sow by Aug 08.

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
0.9″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 105 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 1.5" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 2.8" 0" ❄️ Dormant
Apr 3" 3" 0" ✅ Rainfall sufficient
May 3" 4.4" 0" ✅ Rainfall sufficient
Jun 3" 5.2" 0" ✅ Rainfall sufficient
Jul 3" 4.2" 0" ✅ Rainfall sufficient
Aug 3" 4.2" 0" ✅ Rainfall sufficient
Sep 3" 3.2" 0" ✅ Rainfall sufficient
Oct 3" 2.8" 0.2" 💧 Light watering
Nov 2.6" 0" ❄️ Dormant
Dec 2.1" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Scott 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 ~520 GDD — county provides 2,418 GDD Excellent fit

Mustard Greens Planting Timeline — Scott County, IL

Mustard Greens Planting Calendar

Activity When Date Range
Start Indoors March 10 Mar 10 – Mar 24
Transplant Outdoors April 14 Apr 14 – Apr 28
Direct Sow March 31 Mar 31 – Apr 21
Harvest May 19 May 19 – Jul 21
Fall Sowing August 8 Aug 8 – Aug 22

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

0.7"/week · Only during dry spells

📅 Days to Maturity

30–50 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 6a

📆 Growing Season

186 days in Scott County

Growing Tips for Mustard Greens in Scott County

Direct sow Mustard Greens outdoors after April 14 in Scott County when soil has warmed and frost danger has passed.

Your generous 186.0-day season in Scott 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 Scott County, IL?

Scott County is in Zone 6a with an average last frost of April 14. Plan your Mustard Greens planting based on this frost date — see the calendar above for exact timing.

What planting zone is Scott County, IL?

Scott County, Illinois is in USDA Hardiness Zone 6a. The average last spring frost is April 14 and first fall frost is October 17.

🌱

Your Scott County Garden Planner — Free

A 24-page printable planner built for Scott County (Zone 6a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Scott County, IL. 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.