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When to plant Kai Lan in St. Johns County, FL

St. Johns County's spring Kai Lan window runs January 19 through February 9. aim for a steady week of warm soil before planting. A second sowing from October 7 to October 21 extends the harvest into fall.

When to Plant Kai Lan in St. Johns County, FL

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.

St. Johns County, Florida is in USDA Zone 9b. The average last spring frost is February 9 and the first fall frost is December 2, giving you a growing season of approximately 296 days.

At an elevation of 57 feet, St. Johns County receives approximately 51.1 inches of rainfall annually with predominantly sand soil. Summer highs average 99°F, so Kai Lan may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Kai Lan will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Kai Lan root diseases.

St. Johns County, FL (Zone 9b) Year-round
296 days
Last Spring Frost February 9
296 growing days
First Fall Frost December 2

St. Johns County Soil Profile

Soil Type

Sand

Soil pH

4.9-6.1

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 2.4" 0" ❄️ Dormant
Feb 4.3" 2.4" 1.9" 💧 Light watering
Mar 4.3" 2.8" 1.5" 💧 Light watering
Apr 4.3" 2.8" 1.5" 💧 Light watering
May 4.3" 3.5" 0.8" 💧 Light watering
Jun 4.3" 7" 0" ✅ Rainfall sufficient
Jul 4.3" 7.1" 0" ✅ Rainfall sufficient
Aug 4.3" 7.6" 0" ✅ Rainfall sufficient
Sep 4.3" 6.9" 0" ✅ Rainfall sufficient
Oct 4.3" 4.3" 0" ✅ Rainfall sufficient
Nov 4.3" 2.1" 2.2" 🚿 Regular watering
Dec 4.3" 2.3" 2" 💧 Light watering

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

Kai Lan Planting Timeline — St. Johns County, FL

Kai Lan Planting Calendar

Activity When Date Range
Start Indoors January 12 Jan 12 – Jan 26
Transplant Outdoors February 9 Feb 9 – Feb 23
Direct Sow January 19 Jan 19 – Feb 9
Harvest March 30 Mar 30 – Apr 27
Fall Sowing October 7 Oct 7 – Oct 21

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

Month-by-Month Timeline

MonthActivities
January Start Indoors Direct Sow
February Transplant Outdoors Direct Sow
March Harvest
April Harvest
May
June
July
August
September
October Fall Sowing
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 9b

📆 Growing Season

296 days in St. Johns County

Growing Tips for St. Johns 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 St. Johns County, FL?

St. Johns County is in Zone 9b with an average last frost of February 9. Plan your Kai Lan planting based on this frost date — see the calendar above for exact timing.

What planting zone is St. Johns County, FL?

St. Johns County, Florida is in USDA Hardiness Zone 9b. The average last spring frost is February 9 and first fall frost is December 2.

When should I plant Kai Lan in St. Johns County, FL?

In St. Johns County, FL, plant Kai Lan after the last frost (around February 9) and before the first frost (around December 2). Best results when soil holds above 50°F.

What growing zone is St. Johns County, FL for Kai Lan?

St. Johns County sits in USDA Zone 9b. Kai Lan grows reliably in zones 2a through 11b, so it's a good fit here.

Can Kai Lan grow in St. Johns County's climate?

Yes — Kai Lan grows well in St. Johns County's temperate climate. St. Johns County averages a 297-day frost-free season, with last frost around February 9 and first frost around December 2.

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Your St. Johns County Garden Planner — Free

A 22-page printable planner built for St. Johns County (Zone 9b). 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 St. Johns County, FL. Local conditions may vary. Last updated: July 2026.

Sources & credits

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