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When to Plant Mustard Greens in Kearny County, KS

Kearny County, Kansas Zone 6a May

Kearny County, Kansas gardeners: here's your May plan

If you only do a handful of things in the garden this May, make it these. They're sequenced around your zone's frost timing.

Avg. last frost April 26
Avg. first frost October 16
Soil temp (4") 62°F
Watering High
Pest pressure Low
Daylight 14.1 hrs
  1. Time to start mustard greens inside

    A seed-starting mix and a sunny window (or a grow light) are all you need. Keep soil warm — around 70°F — for fast germination.

  2. Harvest mustard greens as they ripen

    Don't tug. Use scissors or pruners for clean cuts — torn stems invite disease.

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

Kearny County, Kansas is in USDA Zone 6a. The average last spring frost is April 26 and the first fall frost is October 16, giving you a growing season of approximately 173 days.

At an elevation of 720 feet, Kearny County receives approximately 22.9 inches of rainfall annually with predominantly loam soil. Summer highs average 91°F, providing good warmth for Mustard Greens during the growing season.

Kearny County, KS (Zone 6a) Moderate season
173 days
Last Spring Frost April 26
173 growing days
First Fall Frost October 16

Kearny County Soil Profile

Soil Type

Loam

Soil pH

6.7-7.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (78 days to spare)
Start indoors: Mar 13 Transplant: Apr 17 🍅 Harvest: May 22 – Jul 24
Recommended (50%) ✓ Fits season (75 days to spare)
Start indoors: Mar 22 Transplant: Apr 26 🍅 Harvest: May 31 – Aug 2
Safe Start (90%) ✓ Fits season (74 days to spare)
Start indoors: Apr 5 Transplant: May 10 🍅 Harvest: Jun 14 – Aug 16

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 Kearny County

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

Soil pH

Your soil pH (6.7–7.8) is more alkaline than Mustard Greens prefers (6.0–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.2%) — 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

6
successive plantings in your 173-day season

Sow every 3.4 weeks. Last sowing by Aug 27 to harvest before frost.

For a dedicated fall crop, sow by Aug 07.

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
0.6″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 266 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

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 1.8" 0" ❄️ Dormant
Feb 1.4" 0" ❄️ Dormant
Mar 1.8" 0" ❄️ Dormant
Apr 3" 2.5" 0.5" 💧 Light watering
May 3" 2.5" 0.5" 💧 Light watering
Jun 3" 1.6" 1.4" 💧 Light watering
Jul 3" 2.2" 0.8" 💧 Light watering
Aug 3" 2.5" 0.5" 💧 Light watering
Sep 3" 1.9" 1.1" 💧 Light watering
Oct 3" 1.8" 1.2" 💧 Light watering
Nov 1.7" 0" ❄️ Dormant
Dec 1.2" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Kearny 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 ~730 GDD — county provides 3,157 GDD Excellent fit

Mustard Greens Planting Timeline — Kearny County, KS

Mustard Greens Planting Calendar

Activity When Date Range
Start Indoors March 22 Mar 22 – Apr 5
Transplant Outdoors April 26 Apr 26 – May 10
Direct Sow April 12 Apr 12 – May 3
Harvest May 31 May 31 – Aug 2
Fall Sowing August 7 Aug 7 – Aug 21

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

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Start Indoors Transplant Outdoors Direct Sow
May Transplant Outdoors Direct Sow Harvest
June Harvest
July Harvest
August Fall Sowing Harvest
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: too_alkaline

🗺️ USDA Zone

Zone 6a

📆 Growing Season

173 days in Kearny County

Growing Tips for Mustard Greens in Kearny County

Direct sow Mustard Greens outdoors after April 26 in Kearny County when soil has warmed and frost danger has passed.

Your generous 173.0-day season in Kearny 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 Kearny County, KS?

Kearny County is in Zone 6a with an average last frost of April 26. Plan your Mustard Greens planting based on this frost date — see the calendar above for exact timing.

What planting zone is Kearny County, KS?

Kearny County, Kansas is in USDA Hardiness Zone 6a. The average last spring frost is April 26 and first fall frost is October 16.

🌱

Your Kearny County Garden Planner — Free

A 24-page printable planner built for Kearny 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 Kearny County, KS. 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.