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When to Plant Mustard Greens in Crook County, OR

Crook County, Oregon Zone 6a May

This month in Crook County, Oregon

Welcome to May in Zone 6a. These are the moves that will have the biggest impact on your growing season.

Avg. last frost June 9
Avg. first frost September 19
Soil temp (4") 58°F
Watering Critical
Pest pressure Low
Daylight 14.6 hrs
  1. Outdoor sowing time: mustard greens

    Keep the top inch of soil moist until germination — a gentle morning watering for 5–7 days does the job.

June will be here before you know it — start on
  • Transplants going out: 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.

Crook County, Oregon is in USDA Zone 6a. The average last spring frost is June 9 and the first fall frost is September 19, giving you a growing season of approximately 102 days.

At an elevation of 2,233 feet, Crook County receives approximately 21 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Mustard Greens during the growing season.

Crook County, OR (Zone 6a) Short season
102 days
Last Spring Frost June 9
102 growing days
First Fall Frost September 19
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Crook County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (5 days to spare)
Start indoors: Apr 25 Transplant: May 30 🍅 Harvest: Jul 4 – Sep 5
Recommended (50%) ✓ Fits season (4 days to spare)
Start indoors: May 5 Transplant: Jun 9 🍅 Harvest: Jul 14 – Sep 15
Safe Start (90%) ✓ Fits season (8 days to spare)
Start indoors: May 18 Transplant: Jun 22 🍅 Harvest: Jul 27 – Sep 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 Crook County

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

Soil pH

Your soil pH (5.7–6.7) overlaps with Mustard Greens's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (5.6%) — 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

4
successive plantings in your 102-day season

Sow every 3.4 weeks. Last sowing by Jul 31 to harvest before frost.

For a dedicated fall crop, sow by Jul 11.

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
0.9″/week
Watering frequency Natural rainfall sufficient
Season total 0 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 3.4" 0" ❄️ Dormant
Feb 2.2" 0" ❄️ Dormant
Mar 2.2" 0" ❄️ Dormant
Apr 1.5" 0" ❄️ Dormant
May 1.2" 0" ❄️ Dormant
Jun 3" 0.9" 2.1" 🚿 Regular watering
Jul 3" 0.3" 2.7" 🚿 Regular watering
Aug 3" 0.4" 2.6" 🚿 Regular watering
Sep 3" 1" 2" 🚿 Regular watering
Oct 1.6" 0" ❄️ Dormant
Nov 3.1" 0" ❄️ Dormant
Dec 3.1" 0" ❄️ Dormant

Water needs are for active growing months only (Jun–Sep in Crook 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 ~550 GDD — county provides 1,402 GDD Excellent fit

Mustard Greens Planting Timeline — Crook County, OR

Mustard Greens Planting Calendar

Activity When Date Range
Start Indoors May 5 May 5 – May 19
Transplant Outdoors June 9 Jun 9 – Jun 23
Direct Sow May 26 May 26 – Jun 16
Harvest July 14 Jul 14 – Sep 15
Fall Sowing July 11 Jul 11 – Jul 25

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

Month-by-Month Timeline

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

🗺️ USDA Zone

Zone 6a

📆 Growing Season

102 days in Crook County

Growing Tips for Mustard Greens in Crook County

Direct sow Mustard Greens outdoors after June 09 in Crook 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

  • Strawberries

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Mustard Greens in Crook County, OR?

Crook County is in Zone 6a with an average last frost of June 9. Plan your Mustard Greens planting based on this frost date — see the calendar above for exact timing.

What planting zone is Crook County, OR?

Crook County, Oregon is in USDA Hardiness Zone 6a. The average last spring frost is June 9 and first fall frost is September 19.

🌱

Your Crook County Garden Planner — Free

A 24-page printable planner built for Crook 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 Crook County, OR. 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.