Blog

When to Plant Mustard Greens in Macon County, IL

Macon County, Illinois Zone 6a May

May in Macon County, Illinois — your action list

A quick May briefing for Macon County, Illinois gardeners — what's urgent, what's next, and what can wait.

Avg. last frost April 13
Avg. first frost October 19
Soil temp (4") 57°F
Watering Moderate
Pest pressure Low
Daylight 14.2 hrs
  1. Indoor seed-starting week for mustard greens

    Starting these indoors now means sturdy transplants ready the moment your soil warms up.

  2. Start harvesting mustard greens

    The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.

June will be here before you know it — start on
  • 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.

Macon County, Illinois is in USDA Zone 6a. The average last spring frost is April 13 and the first fall frost is October 19, giving you a growing season of approximately 189 days.

At an elevation of 1,064 feet, Macon County receives approximately 31.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Mustard Greens during the growing season.

Macon County, IL (Zone 6a) Moderate season
189 days
Last Spring Frost April 13
189 growing days
First Fall Frost October 19

Macon 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 (91 days to spare)
Start indoors: Mar 3 Transplant: Apr 7 🍅 Harvest: May 12 – Jul 14
Recommended (50%) ✓ Fits season (91 days to spare)
Start indoors: Mar 9 Transplant: Apr 13 🍅 Harvest: May 18 – Jul 20
Safe Start (90%) ✓ Fits season (94 days to spare)
Start indoors: Mar 20 Transplant: Apr 24 🍅 Harvest: May 29 – Jul 31

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 Macon 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 Macon County is excellent for Mustard Greens — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is excellent (4.3%) — 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 189-day season

Sow every 3.4 weeks. Last sowing by Aug 30 to harvest before frost.

For a dedicated fall crop, sow by Aug 10.

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
0.7″/week
Watering frequency Only during dry spells
Season total 7 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 1.3" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 2.2" 0" ❄️ Dormant
Apr 3" 2.9" 0.1" 💧 Light watering
May 3" 3.1" 0" ✅ Rainfall sufficient
Jun 3" 4.1" 0" ✅ Rainfall sufficient
Jul 3" 3.5" 0" ✅ Rainfall sufficient
Aug 3" 3.5" 0" ✅ Rainfall sufficient
Sep 3" 2.9" 0.1" 💧 Light watering
Oct 3" 2.3" 0.7" 💧 Light watering
Nov 2.4" 0" ❄️ Dormant
Dec 1.6" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Macon 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 ~580 GDD — county provides 2,740 GDD Excellent fit

Mustard Greens Planting Timeline — Macon County, IL

Mustard Greens Planting Calendar

Activity When Date Range
Start Indoors March 9 Mar 9 – Mar 23
Transplant Outdoors April 13 Apr 13 – Apr 27
Direct Sow March 30 Mar 30 – Apr 20
Harvest May 18 May 18 – Jul 20
Fall Sowing August 10 Aug 10 – Aug 24

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

189 days in Macon County

Growing Tips for Mustard Greens in Macon County

Direct sow Mustard Greens outdoors after April 13 in Macon County when soil has warmed and frost danger has passed.

Your generous 189.0-day season in Macon 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 Macon County, IL?

Macon County is in Zone 6a with an average last frost of April 13. Plan your Mustard Greens planting based on this frost date — see the calendar above for exact timing.

What planting zone is Macon County, IL?

Macon County, Illinois is in USDA Hardiness Zone 6a. The average last spring frost is April 13 and first fall frost is October 19.

🌱

Your Macon County Garden Planner — Free

A 24-page printable planner built for Macon 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.

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 Macon 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.