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When to Plant Bok Choy in Sumter County, SC

Sumter County, South Carolina Zone 8b May

Your May gardening checklist

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

Avg. last frost March 20
Avg. first frost November 15
Soil temp (4") 74°F
Watering Low
Pest pressure High
Daylight 13.8 hrs
  1. Bring in the bok choy

    This is the payoff month. Bring a basket, bring a friend, and get into the beds.

Before June arrives, get these ready
  • First harvests: bok choy

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Bok choy is a Chinese cabbage variety with crisp white stalks and dark green leaves. It is a fast-growing cool-season crop ideal for stir-fries and soups.

Sumter County, South Carolina is in USDA Zone 8b. The average last spring frost is March 20 and the first fall frost is November 15, giving you a growing season of approximately 240 days.

At an elevation of 163 feet, Sumter County receives approximately 59.6 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 97°F, so Bok Choy may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Bok Choy will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Bok Choy root diseases.

Sumter County, SC (Zone 8b) Long season
240 days
Last Spring Frost March 20
240 growing days
First Fall Frost November 15
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Sumter County Soil Profile

Soil Type

Sandy Loam

Soil pH

4.9-6.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (165 days to spare)
Start indoors: Feb 2 Transplant: Mar 9 🍅 Harvest: Apr 20 – May 25
Recommended (50%) ✓ Fits season (163 days to spare)
Start indoors: Feb 13 Transplant: Mar 20 🍅 Harvest: May 1 – Jun 5
Safe Start (90%) ✓ Fits season (162 days to spare)
Start indoors: Feb 26 Transplant: Apr 2 🍅 Harvest: May 14 – Jun 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 Sumter County

How your county's soil matches Bok Choy's growing requirements.

Soil pH

Your soil pH (4.9–6.3) is more acidic than Bok Choy prefers (6.0–7.5). Add garden lime to raise pH.

Soil Texture

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

Drainage

Drainage is adequate for Bok Choy.

Organic Matter

Organic matter is moderate (2.3%). Annual compost additions will help Bok Choy.

How to Plant Bok Choy

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

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

Succession Planting Bok Choy

7
successive plantings in your 240-day season

Sow every 4.6 weeks. Last sowing by Sep 16 to harvest before frost.

For a dedicated fall crop, sow by Sep 06.

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 Bok Choy

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

Month Bok Choy Needs Rainfall You Supplement Action
Jan 4.8" 0" ❄️ Dormant
Feb 5.4" 0" ❄️ Dormant
Mar 3" 5.1" 0" ✅ Rainfall sufficient
Apr 3" 4.4" 0" ✅ Rainfall sufficient
May 3" 5.5" 0" ✅ Rainfall sufficient
Jun 3" 5.2" 0" ✅ Rainfall sufficient
Jul 3" 7" 0" ✅ Rainfall sufficient
Aug 3" 5.3" 0" ✅ Rainfall sufficient
Sep 3" 4.5" 0" ✅ Rainfall sufficient
Oct 3" 3.3" 0" ✅ Rainfall sufficient
Nov 3" 4.2" 0" ✅ Rainfall sufficient
Dec 5.1" 0" ❄️ Dormant

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

Bok Choy 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.

Bok Choy needs ~1,138 GDD — county provides 5,460 GDD Excellent fit

Bok Choy Planting Timeline — Sumter County, SC

Bok Choy Planting Calendar

Activity When Date Range
Start Indoors February 13 Feb 13 – Feb 27
Transplant Outdoors March 20 Mar 20 – Apr 3
Direct Sow March 6 Mar 6 – Mar 27
Harvest May 1 May 1 – Jun 5
Fall Sowing September 6 Sep 6 – Sep 20

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

Month-by-Month Timeline

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

40–60 days

🧪 Soil pH

Needs 6–7.5 · Your soil: too_acidic

🗺️ USDA Zone

Zone 8b

📆 Growing Season

240 days in Sumter County

Growing Tips for Bok Choy in Sumter County

Direct sow Bok Choy outdoors after March 20 in Sumter County when soil has warmed and frost danger has passed.

Sandy soil in Sumter County dries quickly — mulch Bok Choy 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 Sumter County, provide afternoon shade for Bok Choy and water deeply in the morning.

Your generous 240.0-day season in Sumter County allows multiple plantings of Bok Choy. Sow every 20.0 days for continuous harvest.

Common pests for Bok Choy 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 for best results. Keep soil consistently moist. Harvest whole heads or cut outer leaves for a cut-and-come-again approach.

Companion Planting

Good Companions

Avoid Planting Near

  • Strawberries

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Bok Choy in Sumter County, SC?

Sumter County is in Zone 8b with an average last frost of March 20. Plan your Bok Choy planting based on this frost date — see the calendar above for exact timing.

What planting zone is Sumter County, SC?

Sumter County, South Carolina is in USDA Hardiness Zone 8b. The average last spring frost is March 20 and first fall frost is November 15.

🌱

Your Sumter County Garden Planner — Free

A 24-page printable planner built for Sumter County (Zone 8b). 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 Sumter 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.