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When to Plant Bok Choy in King County, TX

King County, Texas Zone 8a May

May in King County, Texas — your action list

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 March 31
Avg. first frost November 7
Soil temp (4") 62°F
Watering High
Pest pressure Moderate
Daylight 13.7 hrs
  1. Start bok choy indoors

    Label every cell. You will absolutely forget which is which otherwise.

  2. Harvest bok choy as they ripen

    The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.

Coming up in June — start thinking about
  • 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.

King County, Texas is in USDA Zone 8a. The average last spring frost is March 31 and the first fall frost is November 7, giving you a growing season of approximately 221 days.

At an elevation of 3,170 feet, King County receives approximately 60.2 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 99°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.

King County, TX (Zone 8a) Long season
221 days
Last Spring Frost March 31
221 growing days
First Fall Frost November 7
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King County Soil Profile

Soil Type

Sandy Loam

Soil pH

7.8-8.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (145 days to spare)
Start indoors: Feb 16 Transplant: Mar 23 🍅 Harvest: May 4 – Jun 8
Recommended (50%) ✓ Fits season (144 days to spare)
Start indoors: Feb 24 Transplant: Mar 31 🍅 Harvest: May 12 – Jun 16
Safe Start (90%) ✓ Fits season (144 days to spare)
Start indoors: Mar 11 Transplant: Apr 15 🍅 Harvest: May 27 – Jul 1

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 King County

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

Soil pH

Your soil pH (7.8–8.4) is more alkaline than Bok Choy prefers (6.0–7.5). Add sulfur or peat moss to lower pH.

Soil Texture

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

Organic Matter

Organic matter is low (1.1%). Add 2-3 inches of compost before planting 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

6
successive plantings in your 221-day season

Sow every 4.6 weeks. Last sowing by Sep 08 to harvest before frost.

For a dedicated fall crop, sow by Aug 29.

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
1.1″/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 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 4.7" 0" ❄️ Dormant
Feb 3.2" 0" ❄️ Dormant
Mar 3" 3.9" 0" ✅ Rainfall sufficient
Apr 3" 2.3" 0.7" 💧 Light watering
May 3" 1.5" 1.5" 🚿 Regular watering
Jun 3" 2.2" 0.8" 💧 Light watering
Jul 3" 10.4" 0" ✅ Rainfall sufficient
Aug 3" 11.5" 0" ✅ Rainfall sufficient
Sep 3" 8.1" 0" ✅ Rainfall sufficient
Oct 3" 5.7" 0" ✅ Rainfall sufficient
Nov 3" 3" 0" ✅ Rainfall sufficient
Dec 3.7" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in King 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 ~1,212 GDD — county provides 5,359 GDD Excellent fit

Bok Choy Planting Timeline — King County, TX

Bok Choy Planting Calendar

Activity When Date Range
Start Indoors February 24 Feb 24 – Mar 10
Transplant Outdoors March 31 Mar 31 – Apr 14
Direct Sow March 17 Mar 17 – Apr 7
Harvest May 12 May 12 – Jun 16
Fall Sowing August 29 Aug 29 – Sep 12

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

Month-by-Month Timeline

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

🗺️ USDA Zone

Zone 8a

📆 Growing Season

221 days in King County

Growing Tips for Bok Choy in King County

Direct sow Bok Choy outdoors after March 31 in King County when soil has warmed and frost danger has passed.

Sandy soil in King 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 99°F in King County, provide afternoon shade for Bok Choy and water deeply in the morning.

Your generous 221.0-day season in King 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 King County, TX?

King County is in Zone 8a with an average last frost of March 31. Plan your Bok Choy planting based on this frost date — see the calendar above for exact timing.

What planting zone is King County, TX?

King County, Texas is in USDA Hardiness Zone 8a. The average last spring frost is March 31 and first fall frost is November 7.

🌱

Your King County Garden Planner — Free

A 24-page printable planner built for King County (Zone 8a). 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 King County, TX. 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.