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When to Plant Kohlrabi in Brule County, SD

Brule County, South Dakota Zone 5a May

Your May planting checklist for Brule County, South Dakota

May rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Brule County, South Dakota.

Avg. last frost May 6
Avg. first frost October 6
Soil temp (4") 56°F
Watering Low
Pest pressure Low
Daylight 14.5 hrs
  1. Transplant kohlrabi outside

    Harden off for 7 days — a little more sun each day — before planting. That's the difference between a seedling that thrives and one that stalls.

A few tasks this May that'll pay off in June
  • Starting indoors: kohlrabi
  • First harvests: 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.

Brule County, South Dakota is in USDA Zone 5a. The average last spring frost is May 6 and the first fall frost is October 6, giving you a growing season of approximately 153 days.

At an elevation of 661 feet, Brule County receives approximately 29.2 inches of rainfall annually with predominantly loam soil. Summer highs average 80°F, so choose short-season varieties of Kohlrabi to ensure they mature before fall.

Brule County, SD (Zone 5a) Moderate season
153 days
Last Spring Frost May 6
153 growing days
First Fall Frost October 6
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Brule County Soil Profile

Soil Type

Loam

Soil pH

6.3-7.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (74 days to spare)
Start indoors: Mar 23 Transplant: Apr 27 🍅 Harvest: Jun 15 – Jul 20
Recommended (50%) ✓ Fits season (69 days to spare)
Start indoors: Apr 1 Transplant: May 6 🍅 Harvest: Jun 24 – Jul 29
Safe Start (90%) ✓ Fits season (66 days to spare)
Start indoors: Apr 13 Transplant: May 18 🍅 Harvest: Jul 6 – Aug 10

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 Brule County

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

Soil pH

Your soil pH (6.3–7.9) overlaps with Kohlrabi's range (6.0–7.5), though not a perfect match.

Soil Texture

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

Drainage

Drainage is adequate for Kohlrabi.

Organic Matter

Organic matter is excellent (4.2%) — 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

4
successive plantings in your 153-day season

Sow every 5.1 weeks. Last sowing by Aug 02 to harvest before frost.

For a dedicated fall crop, sow by Jul 28.

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
0.8″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 177 gal / 100 sq ft
Drought risk

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

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 0.7" 0" ❄️ Dormant
Feb 1" 0" ❄️ Dormant
Mar 1.9" 0" ❄️ Dormant
Apr 2.8" 0" ❄️ Dormant
May 3" 4.8" 0" ✅ Rainfall sufficient
Jun 3" 4.6" 0" ✅ Rainfall sufficient
Jul 3" 3.3" 0" ✅ Rainfall sufficient
Aug 3" 4" 0" ✅ Rainfall sufficient
Sep 3" 2.5" 0.5" 💧 Light watering
Oct 3" 1.7" 1.3" 💧 Light watering
Nov 1.1" 0" ❄️ Dormant
Dec 0.8" 0" ❄️ Dormant

Water needs are for active growing months only (May–Oct in Brule 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 ~550 GDD — county provides 1,530 GDD Excellent fit

Kohlrabi Planting Timeline — Brule County, SD

Kohlrabi Planting Calendar

Activity When Date Range
Start Indoors April 1 Apr 1 – Apr 15
Transplant Outdoors May 6 May 6 – May 20
Direct Sow April 22 Apr 22 – May 13
Harvest June 24 Jun 24 – Jul 29
Fall Sowing July 28 Jul 28 – Aug 11

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

Month-by-Month Timeline

MonthActivities
January
February
March
April Start Indoors Direct Sow
May Transplant Outdoors Direct Sow
June Harvest
July Fall Sowing Harvest
August Fall Sowing
September
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 5a

📆 Growing Season

153 days in Brule County

Growing Tips for Kohlrabi in Brule County

Direct sow Kohlrabi outdoors after May 06 in Brule 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 Brule County, SD?

Brule County is in Zone 5a with an average last frost of May 6. Plan your Kohlrabi planting based on this frost date — see the calendar above for exact timing.

What planting zone is Brule County, SD?

Brule County, South Dakota is in USDA Hardiness Zone 5a. The average last spring frost is May 6 and first fall frost is October 6.

🌱

Your Brule County Garden Planner — Free

A 24-page printable planner built for Brule County (Zone 5a). 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 Brule County, SD. 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.