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When to Plant Kale in Harney County, OR

Harney County, Oregon Zone 6a May

What to do in May

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 June 17
Avg. first frost September 6
Soil temp (4") 60°F
Watering High
Pest pressure Low
Daylight 14.5 hrs
June prep starts now
  • Transplants going out: kale
  • Direct-sowing: kale
  • Fall sowing: kale

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Kale is an exceptionally hardy, nutrient-dense green available in curly, lacinato, and Russian varieties. It tolerates heavy frost and often tastes sweeter after cold exposure.

Harney County, Oregon is in USDA Zone 6a. The average last spring frost is June 17 and the first fall frost is September 6, giving you a growing season of approximately 81 days.

At an elevation of 679 feet, Harney County receives approximately 22.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Kale during the growing season.

Harney County, OR (Zone 6a) Very short season
81 days
Last Spring Frost June 17
81 growing days
First Fall Frost September 6

Harney County Soil Profile

Soil Type

Silt Loam

Soil pH

5.6-6.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: May 8 Transplant: Jun 12 🍅 Harvest: Aug 7 – Oct 2
Recommended (50%) ✗ May not fit
Start indoors: May 13 Transplant: Jun 17 🍅 Harvest: Aug 12 – Oct 7
Safe Start (90%) ✗ May not fit
Start indoors: May 20 Transplant: Jun 24 🍅 Harvest: Aug 19 – Oct 14

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 Harney County

How your county's soil matches Kale's growing requirements.

Soil pH

Your soil pH (5.6–6.4) overlaps with Kale's range (6.0–7.5), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (5.5%) — Kale will thrive.

How to Plant Kale

1"
Planting Depth
15"
Between Plants
24"
Between Rows

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

Plant Water Budget

Plant needs
0.8″/week
Rainfall provides
1.2″/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 Kale

Kale needs approximately 0.8 inches of water per week (3.5" per month). Here's how your county's rainfall compares month by month.

Month Kale Needs Rainfall You Supplement Action
Jan 3.3" 0" ❄️ Dormant
Feb 2.2" 0" ❄️ Dormant
Mar 1.9" 0" ❄️ Dormant
Apr 1.5" 0" ❄️ Dormant
May 1.4" 0" ❄️ Dormant
Jun 3.5" 0.9" 2.6" 🚿 Regular watering
Jul 3.5" 0.4" 3.1" 🚿 Regular watering
Aug 3.5" 0.4" 3.1" 🚿 Regular watering
Sep 3.5" 0.9" 2.6" 🚿 Regular watering
Oct 2" 0" ❄️ Dormant
Nov 3.6" 0" ❄️ Dormant
Dec 3.7" 0" ❄️ Dormant

Water needs are for active growing months only (Jun–Sep in Harney County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Kale 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.

Kale needs ~915 GDD — county provides 1,235 GDD Excellent fit

Kale Planting Timeline — Harney County, OR

Kale Planting Calendar

Activity When Date Range
Start Indoors May 13 May 13 – May 27
Transplant Outdoors June 17 Jun 17 – Jul 1
Direct Sow June 3 Jun 3 – Jun 24
Harvest August 12 Aug 12 – Oct 7
Fall Sowing June 28 Jun 28 – Jul 12

Plant 1" deep · 15" apart · Rows 24" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.8"/week · Natural rainfall sufficient

📅 Days to Maturity

50–70 days

🧪 Soil pH

Needs 6–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 6a

📆 Growing Season

81 days in Harney County

Growing Tips for Kale in Harney County

Direct sow Kale outdoors after June 17 in Harney County when soil has warmed and frost danger has passed.

Common pests for Kale 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 or transplant in early spring or late summer. Harvest outer leaves first to keep plants productive. Kale overwinters in many climates and can provide greens all year.

Recommended Kale Varieties for Harney County

Cold-hardy kale that improves in flavor after frost

Winterbor Red Russian Dwarf Blue Curled

Companion Planting

Good Companions

Avoid Planting Near

  • Strawberries
  • Tomatoes

Check more plant combinations with our Companion Planting Checker →

🌾 Save Your Own Kale Seeds
Life Cycle Biennial
Pollination Cross-Pollinated (insects)
How to Collect Allow 2nd year flower stalks to dry. Harvest pods when tan.
Storage Store airtight; viable 5 years at 35°F, under 50% humidity.

Isolate 1/2 mile from other brassicas (broccoli, cabbage, etc.) — they all cross.

Frequently Asked Questions

When should I plant Kale in Harney County, OR?

Harney County is in Zone 6a with an average last frost of June 17. Plan your Kale planting based on this frost date — see the calendar above for exact timing.

What planting zone is Harney County, OR?

Harney County, Oregon is in USDA Hardiness Zone 6a. The average last spring frost is June 17 and first fall frost is September 6.

🌱

Your Harney County Garden Planner — Free

A 24-page printable planner built for Harney 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 Harney 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.