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When to Plant Kohlrabi in Jasper County, SC

Jasper County, South Carolina Zone 9a May

This month in Jasper County, South Carolina

Your garden in Jasper County, South Carolina is working on a schedule, even when you're not. Here's where you should be this May.

Avg. last frost March 15
Avg. first frost November 12
Soil temp (4") 74°F
Watering Low
Pest pressure High
Daylight 13.7 hrs
  1. Bring in the kohlrabi

    Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.

Before June arrives, get these ready
  • 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.

Jasper County, South Carolina is in USDA Zone 9a. The average last spring frost is March 15 and the first fall frost is November 12, giving you a growing season of approximately 242 days.

At an elevation of 143 feet, Jasper County receives approximately 60.1 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 97°F, so Kohlrabi may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Kohlrabi will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Kohlrabi root diseases.

Jasper County, SC (Zone 9a) Long season
242 days
Last Spring Frost March 15
242 growing days
First Fall Frost November 12

Jasper County Soil Profile

Soil Type

Sandy Loam

Soil pH

4.8-6.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (161 days to spare)
Start indoors: Feb 6 Transplant: Mar 6 🍅 Harvest: Apr 24 – May 29
Recommended (50%) ✓ Fits season (158 days to spare)
Start indoors: Feb 15 Transplant: Mar 15 🍅 Harvest: May 3 – Jun 7
Safe Start (90%) ✓ Fits season (153 days to spare)
Start indoors: Mar 12 Transplant: Apr 9 🍅 Harvest: May 28 – Jul 2

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 Jasper County

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

Soil pH

Your soil pH (4.8–6.2) is more acidic than Kohlrabi prefers (6.0–7.5). Add garden lime to raise pH.

Soil Texture

Sandy soil in Jasper County warms quickly in spring but drains fast. Kohlrabi will need more frequent watering and regular compost additions to retain nutrients.

Drainage

Drainage is adequate for Kohlrabi.

Organic Matter

Organic matter is moderate (2.1%). Annual compost additions will help Kohlrabi.

How to Plant Kohlrabi

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

Fall planting: Sow 8 weeks before your first frost date for a fall harvest.

Succession Planting Kohlrabi

6
successive plantings in your 242-day season

Sow every 5.1 weeks. Last sowing by Sep 08 to harvest before frost.

For a dedicated fall crop, sow by Sep 17.

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
1.0″/week
Watering frequency Natural rainfall sufficient
Season total 0 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 4.6" 0" ❄️ Dormant
Feb 4.8" 0" ❄️ Dormant
Mar 3" 5.7" 0" ✅ Rainfall sufficient
Apr 3" 4.3" 0" ✅ Rainfall sufficient
May 3" 5.5" 0" ✅ Rainfall sufficient
Jun 3" 5.2" 0" ✅ Rainfall sufficient
Jul 3" 5.8" 0" ✅ Rainfall sufficient
Aug 3" 5.1" 0" ✅ Rainfall sufficient
Sep 3" 5" 0" ✅ Rainfall sufficient
Oct 3" 3.5" 0" ✅ Rainfall sufficient
Nov 3" 5.3" 0" ✅ Rainfall sufficient
Dec 5.2" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Jasper 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 ~1,251 GDD — county provides 5,505 GDD Excellent fit

Kohlrabi Planting Timeline — Jasper County, SC

Kohlrabi Planting Calendar

Activity When Date Range
Start Indoors February 15 Feb 15 – Mar 1
Transplant Outdoors March 15 Mar 15 – Mar 29
Direct Sow February 22 Feb 22 – Mar 15
Harvest May 3 May 3 – Jun 7
Fall Sowing September 17 Sep 17 – Oct 1

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.7"/week · Natural rainfall sufficient

📅 Days to Maturity

45–65 days

🧪 Soil pH

Needs 6–7.5 · Your soil: too_acidic

🗺️ USDA Zone

Zone 9a

📆 Growing Season

242 days in Jasper County

Growing Tips for Kohlrabi in Jasper County

Direct sow Kohlrabi outdoors after March 15 in Jasper County when soil has warmed and frost danger has passed.

Sandy soil in Jasper County dries quickly — mulch Kohlrabi with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

With summer highs reaching 97°F in Jasper County, provide afternoon shade for Kohlrabi and water deeply in the morning.

Your generous 242.0-day season in Jasper County allows multiple plantings of Kohlrabi. Sow every 22.0 days for continuous harvest.

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 Jasper County, SC?

Jasper County is in Zone 9a with an average last frost of March 15. Plan your Kohlrabi planting based on this frost date — see the calendar above for exact timing.

What planting zone is Jasper County, SC?

Jasper County, South Carolina is in USDA Hardiness Zone 9a. The average last spring frost is March 15 and first fall frost is November 12.

🌱

Your Jasper County Garden Planner — Free

A 24-page printable planner built for Jasper County (Zone 9a). 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 Jasper County, SC. 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.