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When to Plant Kai Lan in Monmouth County, NJ

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.

Monmouth County, New Jersey is in USDA Zone 7a. The average last spring frost is March 29 and the first fall frost is November 12, giving you a growing season of approximately 228 days.

At an elevation of 280 feet, Monmouth County receives approximately 39 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89ยฐF, providing good warmth for Kai Lan during the growing season.

Monmouth County, NJ (Zone 7a) Long season
228 days
Last Spring Frost March 29
228 growing days
First Fall Frost November 12

Monmouth County Soil Profile

Soil Type

Silt Loam

Soil pH

5-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (151 days to spare)
Start indoors: Feb 18 Transplant: Mar 25 🍅 Harvest: May 13 – Jun 10
Recommended (50%) ✓ Fits season (151 days to spare)
Start indoors: Feb 22 Transplant: Mar 29 🍅 Harvest: May 17 – Jun 14
Safe Start (90%) ✓ Fits season (160 days to spare)
Start indoors: Mar 5 Transplant: Apr 9 🍅 Harvest: May 28 – Jun 25

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 Monmouth County

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

Soil pH

Your soil pH (5.0โ€“6.8) is more acidic than Kai Lan prefers (6.0โ€“7.5). Add garden lime to raise pH.

Soil Texture

The silt loam soil in Monmouth County is excellent for Kai Lan โ€” good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Kai Lan.

Organic Matter

Organic matter is moderate (3.8%). 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

6
successive plantings in your 228-day season

Sow every 5.1 weeks. Last sowing by Sep 13 to harvest before frost.

For a dedicated fall crop, sow by Sep 03.

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 โ€” 2.7" 0" โ„๏ธ Dormant
Feb โ€” 2.5" 0" โ„๏ธ Dormant
Mar 4.3" 3.6" 0.7" ๐Ÿ’ง Light watering
Apr 4.3" 3.8" 0.5" ๐Ÿ’ง Light watering
May 4.3" 3.6" 0.7" ๐Ÿ’ง Light watering
Jun 4.3" 3.2" 1.1" ๐Ÿ’ง Light watering
Jul 4.3" 4" 0.3" ๐Ÿ’ง Light watering
Aug 4.3" 3.6" 0.7" ๐Ÿ’ง Light watering
Sep 4.3" 3.2" 1.1" ๐Ÿ’ง Light watering
Oct 4.3" 3.2" 1.1" ๐Ÿ’ง Light watering
Nov 4.3" 2.6" 1.7" ๐Ÿ’ง Light watering
Dec โ€” 3" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Marโ€“Nov in Monmouth County). Supplement amounts are based on average rainfall โ€” 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" โ€” every day above 50ยฐF 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 ~879 GDD — county provides 3,819 GDD Excellent fit

Kai Lan Planting Timeline โ€” Monmouth County, NJ

Kai Lan Planting Calendar

Activity When Date Range
Start Indoors February 22 Feb 22 โ€“ Mar 8
Transplant Outdoors March 29 Mar 29 โ€“ Apr 12
Direct Sow March 15 Mar 15 โ€“ Apr 5
Harvest May 17 May 17 โ€“ Jun 14
Fall Sowing September 3 Sep 3 โ€“ Sep 17

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

45โ€“60 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 7a

๐Ÿ“† Growing Season

228 days in Monmouth County

Growing Tips for Kai Lan in Monmouth County

Direct sow Kai Lan outdoors after March 29 in Monmouth County when soil has warmed and frost danger has passed.

Your generous 228.0-day season in Monmouth 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 Monmouth County, NJ?

Monmouth County is in Zone 7a with an average last frost of March 29. Plan your Kai Lan planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Monmouth County, NJ?

Monmouth County, New Jersey is in USDA Hardiness Zone 7a. The average last spring frost is March 29 and first fall frost is November 12.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Monmouth County gardeners in Zone 7a organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

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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 Monmouth County, NJ. Local conditions may vary. Last updated: April 2026.