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When to Plant Kai Lan in St. Helena Parish, LA

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. Helena Parish, Louisiana is in USDA Zone 8b. The average last spring frost is March 5 and the first fall frost is November 30, giving you a growing season of approximately 270 days.

At an elevation of 437 feet, St. Helena Parish receives approximately 50 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 96ยฐF, so Kai Lan may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring โ€” great for early planting โ€” but Kai Lan will need more frequent watering and organic matter to retain nutrients.

St. Helena Parish, LA (Zone 8b) Year-round
270 days
Last Spring Frost March 5
270 growing days
First Fall Frost November 30

St. Helena Parish Soil Profile

Soil Type

Sandy Loam

Soil pH

4.8-6.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (201 days to spare)
Start indoors: Jan 11 Transplant: Feb 15 🍅 Harvest: Apr 5 – May 3
Recommended (50%) ✓ Fits season (193 days to spare)
Start indoors: Jan 29 Transplant: Mar 5 🍅 Harvest: Apr 23 – May 21
Safe Start (90%) ✓ Fits season (187 days to spare)
Start indoors: Feb 19 Transplant: Mar 26 🍅 Harvest: May 14 – Jun 11

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.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.8″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 534 gal / 100 sq ft
Kai Lan needs ~1,155 GDD — county provides 5,940 GDD Excellent fit

Kai Lan Planting Timeline โ€” St. Helena Parish, LA

Kai Lan Planting Calendar

Activity When Date Range
Start Indoors January 29 Jan 29 โ€“ Feb 12
Transplant Outdoors March 5 Mar 5 โ€“ Mar 19
Direct Sow February 19 Feb 19 โ€“ Mar 12
Fall Sowing September 21 Sep 21 โ€“ Oct 5
Harvest April 23 Apr 23 โ€“ May 21

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

Month-by-Month Timeline

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

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

45โ€“60 days

Soil pH

6 โ€“ 7.5

USDA Zone

Zone 8b

Growing Season

270 days

Growing Tips for St. Helena Parish

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

Level Up Your Garden

Frequently Asked Questions

When should I plant Kai Lan in St. Helena Parish, LA?

St. Helena Parish is in Zone 8b with an average last frost of March 5. Plan your Kai Lan planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is St. Helena Parish, LA?

St. Helena Parish, Louisiana is in USDA Hardiness Zone 8b. The average last spring frost is March 5 and first fall frost is November 30.

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Plan Your Garden with Confidence

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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. Helena Parish, LA. Local conditions may vary. Last updated: April 2026.