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When to Plant Kai Lan in Prince George's County, MD

Prince George's County, Maryland Zone 7b May

This month in Prince George's County, Maryland

A quick May briefing for Prince George's County, Maryland gardeners — what's urgent, what's next, and what can wait.

Avg. last frost April 1
Avg. first frost November 10
Soil temp (4") 68°F
Watering Moderate
Pest pressure Moderate
Daylight 14.1 hrs
  1. Fire up the seed-starting tray: kai lan

    Your window is short. These crops want several weeks of indoor growth before they go outside.

  2. Collect kai lan at their peak

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

Coming up in June — start thinking about
  • First harvests: kai lan

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Kai lan (Chinese broccoli) is a brassica grown for its thick, glossy stems and small flower buds. It has a slightly bitter, broccoli-like flavor essential in Cantonese cooking.

Prince George's County, Maryland is in USDA Zone 7b. The average last spring frost is April 1 and the first fall frost is November 10, giving you a growing season of approximately 223 days.

At an elevation of 322 feet, Prince George's County receives approximately 39.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90°F, providing good warmth for Kai Lan during the growing season.

Prince George's County, MD (Zone 7b) Long season
223 days
Last Spring Frost April 1
223 growing days
First Fall Frost November 10

Prince George's County Soil Profile

Soil Type

Silt Loam

Soil pH

5.3-6.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (145 days to spare)
Start indoors: Feb 19 Transplant: Mar 26 🍅 Harvest: May 14 – Jun 11
Recommended (50%) ✓ Fits season (146 days to spare)
Start indoors: Feb 25 Transplant: Apr 1 🍅 Harvest: May 20 – Jun 17
Safe Start (90%) ✓ Fits season (159 days to spare)
Start indoors: Mar 13 Transplant: Apr 17 🍅 Harvest: Jun 5 – Jul 3

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 Prince George's County

How your county's soil matches Kai Lan's growing requirements.

Soil pH

Your soil pH (5.3–6.9) overlaps with Kai Lan's range (6.0–7.5), though not a perfect match.

Soil Texture

The silt loam soil in Prince George's County is excellent for Kai Lan — good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Kai Lan.

Organic Matter

Organic matter is moderate (3.0%). Annual compost additions will help Kai Lan.

How to Plant Kai Lan

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

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

Succession Planting Kai Lan

5
successive plantings in your 223-day season

Sow every 5.1 weeks. Last sowing by Sep 11 to harvest before frost.

For a dedicated fall crop, sow by Sep 01.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.7″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Kai Lan

Kai Lan needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Kai Lan Needs Rainfall You Supplement Action
Jan 2.4" 0" ❄️ Dormant
Feb 2.5" 0" ❄️ Dormant
Mar 3.4" 0" ❄️ Dormant
Apr 4.3" 3.7" 0.6" 💧 Light watering
May 4.3" 3.6" 0.7" 💧 Light watering
Jun 4.3" 3.6" 0.7" 💧 Light watering
Jul 4.3" 3.3" 1" 💧 Light watering
Aug 4.3" 3.4" 0.9" 💧 Light watering
Sep 4.3" 3.6" 0.7" 💧 Light watering
Oct 4.3" 3.5" 0.8" 💧 Light watering
Nov 4.3" 3.2" 1.1" 💧 Light watering
Dec 3" 0" ❄️ Dormant

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

Kai Lan 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.

Kai Lan needs ~919 GDD — county provides 3,902 GDD Excellent fit

Kai Lan Planting Timeline — Prince George's County, MD

Kai Lan Planting Calendar

Activity When Date Range
Start Indoors February 25 Feb 25 – Mar 11
Transplant Outdoors April 1 Apr 1 – Apr 15
Direct Sow March 18 Mar 18 – Apr 8
Harvest May 20 May 20 – Jun 17
Fall Sowing September 1 Sep 1 – Sep 15

Plant 0.5" deep · 6" apart · Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Natural rainfall sufficient

📅 Days to Maturity

45–60 days

🧪 Soil pH

Needs 6–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 7b

📆 Growing Season

223 days in Prince George's County

Growing Tips for Kai Lan in Prince George's County

Direct sow Kai Lan outdoors after April 01 in Prince George's County when soil has warmed and frost danger has passed.

Your generous 223.0-day season in Prince George's County allows multiple plantings of Kai Lan. Sow every 22.0 days for continuous harvest.

Common pests for Kai Lan 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 flower buds first appear but before they open. Cut stems at the base to encourage side shoots. Prefers cool weather.

Companion Planting

Good Companions

Avoid Planting Near

  • Strawberries

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Kai Lan in Prince George's County, MD?

Prince George's County is in Zone 7b with an average last frost of April 1. Plan your Kai Lan planting based on this frost date — see the calendar above for exact timing.

What planting zone is Prince George's County, MD?

Prince George's County, Maryland is in USDA Hardiness Zone 7b. The average last spring frost is April 1 and first fall frost is November 10.

🌱

Your Prince George's County Garden Planner — Free

A 24-page printable planner built for Prince George's County (Zone 7b). 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 Prince George's County, MD. 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.