Blog

When to Plant Kai Lan in Johnson County, WY

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.

Johnson County, Wyoming is in USDA Zone 5a. The average last spring frost is May 17 and the first fall frost is September 21, giving you a growing season of approximately 127 days.

At an elevation of 8,281 feet, Johnson County receives approximately 23.7 inches of rainfall annually with predominantly loam soil. Summer highs average 81°F, so choose short-season varieties of Kai Lan to ensure they mature before fall.

Johnson County, WY (Zone 5a) Short season
127 days
Last Spring Frost May 17
127 growing days
First Fall Frost September 21

Johnson County Soil Profile

Soil Type

Loam

Soil pH

6.8-7.8

Drainage

Well Drained

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 1.8" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 1.9" 0" ❄️ Dormant
Apr 2.1" 0" ❄️ Dormant
May 4.3" 2.8" 1.5" 💧 Light watering
Jun 4.3" 1.6" 2.7" 🚿 Regular watering
Jul 4.3" 2.3" 2" 💧 Light watering
Aug 4.3" 2.5" 1.8" 💧 Light watering
Sep 4.3" 2.1" 2.2" 🚿 Regular watering
Oct 2.1" 0" ❄️ Dormant
Nov 1.5" 0" ❄️ Dormant
Dec 1.5" 0" ❄️ Dormant

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

Kai Lan Planting Timeline — Johnson County, WY

Kai Lan Planting Calendar

Activity When Date Range
Start Indoors April 12 Apr 12 – Apr 26
Transplant Outdoors May 17 May 17 – May 31
Direct Sow May 3 May 3 – May 24
Harvest July 5 Jul 5 – Aug 2
Fall Sowing July 13 Jul 13 – Jul 27

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

45–60 days

🧪 Soil pH

Needs 6–7.5 · Your soil: N/A

🗺️ USDA Zone

Zone 5a

📆 Growing Season

127 days in Johnson County

Growing Tips for Johnson County

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 Johnson County, WY?

Johnson County is in Zone 5a with an average last frost of May 17. Plan your Kai Lan planting based on this frost date — see the calendar above for exact timing.

What planting zone is Johnson County, WY?

Johnson County, Wyoming is in USDA Hardiness Zone 5a. The average last spring frost is May 17 and first fall frost is September 21.

🌱

Your Johnson County Garden Planner — Free

A 22-page printable planner built for Johnson County (Zone 5a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Johnson County, WY. Local conditions may vary. Last updated: July 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.