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When to Plant Kohlrabi in Lake County, OR

Lake County, Oregon Zone 6b May

Your May game plan for Lake County, Oregon

Each item below is timed to Lake County, Oregon's frost dates and soil temperatures. Skip nothing, stress about nothing.

Avg. last frost June 16
Avg. first frost September 7
Soil temp (4") 58°F
Watering Critical
Pest pressure Low
Daylight 14.4 hrs
To set up a strong June, finish these tasks
  • Transplants going out: kohlrabi
  • Direct-sowing: kohlrabi
  • Fall sowing: kohlrabi

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Kohlrabi is an unusual brassica that forms a swollen stem above ground with a mild, sweet turnip-like flavor. Both the bulb and tender leaves are edible.

Lake County, Oregon is in USDA Zone 6b. The average last spring frost is June 16 and the first fall frost is September 7, giving you a growing season of approximately 83 days.

At an elevation of 1,236 feet, Lake County receives approximately 12.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88°F, providing good warmth for Kohlrabi during the growing season. With low rainfall, drip irrigation is essential for growing Kohlrabi successfully. Mulch heavily to conserve soil moisture.

Lake County, OR (Zone 6b) Very short season
83 days
Last Spring Frost June 16
83 growing days
First Fall Frost September 7
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Lake County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (5 days to spare)
Start indoors: Apr 28 Transplant: Jun 2 🍅 Harvest: Jul 21 – Aug 25
Recommended (50%) ✗ May not fit
Start indoors: May 12 Transplant: Jun 16 🍅 Harvest: Aug 4 – Sep 8
Safe Start (90%) ✓ Fits season (12 days to spare)
Start indoors: May 22 Transplant: Jun 26 🍅 Harvest: Aug 14 – Sep 18

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 Lake County

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

Soil pH

Your soil pH (5.7–6.4) overlaps with Kohlrabi's range (6.0–7.5), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.4%) — Kohlrabi will thrive.

How to Plant Kohlrabi

0.5"
Planting Depth
4"
Between Plants
12"
Between Rows

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

Succession Planting Kohlrabi

2
successive plantings in your 83-day season

Sow every 5.1 weeks. Last sowing by Jul 04 to harvest before frost.

For a dedicated fall crop, sow by Jun 29.

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
0.7″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 39 gal / 100 sq ft

Monthly Watering Guide for Kohlrabi

Kohlrabi needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.

Month Kohlrabi Needs Rainfall You Supplement Action
Jan 2" 0" ❄️ Dormant
Feb 1.3" 0" ❄️ Dormant
Mar 1.3" 0" ❄️ Dormant
Apr 0.8" 0" ❄️ Dormant
May 0.7" 0" ❄️ Dormant
Jun 3" 0.5" 2.5" 🚿 Regular watering
Jul 3" 0.2" 2.8" 🚿 Regular watering
Aug 3" 0.2" 2.8" 🚿 Regular watering
Sep 3" 0.5" 2.5" 🚿 Regular watering
Oct 1.2" 0" ❄️ Dormant
Nov 1.9" 0" ❄️ Dormant
Dec 2.1" 0" ❄️ Dormant

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

Kohlrabi 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.

Kohlrabi needs ~880 GDD — county provides 1,328 GDD Excellent fit

Kohlrabi Planting Timeline — Lake County, OR

Kohlrabi Planting Calendar

Activity When Date Range
Start Indoors May 12 May 12 – May 26
Transplant Outdoors June 16 Jun 16 – Jun 30
Direct Sow June 2 Jun 2 – Jun 23
Harvest August 4 Aug 4 – Sep 8
Fall Sowing June 29 Jun 29 – Jul 13

Plant 0.5" deep · 4" apart · Rows 12" apart

Month-by-Month Timeline

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

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.7"/week · Only during dry spells

📅 Days to Maturity

45–65 days

🧪 Soil pH

Needs 6–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 6b

📆 Growing Season

83 days in Lake County

Growing Tips for Kohlrabi in Lake County

Direct sow Kohlrabi outdoors after June 16 in Lake County when soil has warmed and frost danger has passed.

Common pests for Kohlrabi 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 spring or fall. Harvest when bulbs are 2-3 inches in diameter for best texture and flavor. Larger bulbs may become woody and fibrous.

Companion Planting

Good Companions

Avoid Planting Near

  • Tomatoes
  • Strawberries

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Kohlrabi in Lake County, OR?

Lake County is in Zone 6b with an average last frost of June 16. Plan your Kohlrabi planting based on this frost date — see the calendar above for exact timing.

What planting zone is Lake County, OR?

Lake County, Oregon is in USDA Hardiness Zone 6b. The average last spring frost is June 16 and first fall frost is September 7.

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Your Lake County Garden Planner — Free

A 24-page printable planner built for Lake County (Zone 6b). 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 Lake 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.