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When to Plant Radish in St. John the Baptist Parish, LA

Radishes are one of the fastest-growing vegetables, with some varieties ready in under a month. They come in round, elongated, and large winter types.

St. John the Baptist Parish, Louisiana is in USDA Zone 9a. The average last spring frost is February 20 and the first fall frost is December 1, giving you a growing season of approximately 284 days.

At an elevation of 309 feet, St. John the Baptist Parish receives approximately 53.7 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 103ยฐF, so Radish may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring โ€” great for early planting โ€” but Radish will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Radish root diseases.

St. John the Baptist Parish, LA (Zone 9a) Year-round
284 days
Last Spring Frost February 20
284 growing days
First Fall Frost December 1

St. John the Baptist Parish Soil Profile

Soil Type

Sandy Loam

Soil pH

4.8-6.1

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (239 days to spare)
Transplant: Feb 6 🍅 Harvest: Mar 6 – Mar 27
Recommended (50%) ✓ Fits season (235 days to spare)
Transplant: Feb 20 🍅 Harvest: Mar 20 – Apr 10
Safe Start (90%) ✓ Fits season (222 days to spare)
Transplant: Mar 22 🍅 Harvest: Apr 19 – May 10

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
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

Radish needs ~777 GDD — county provides 7,766 GDD Excellent fit

Radish Planting Timeline โ€” St. John the Baptist Parish, LA

Radish Planting Calendar

Activity When Date Range
Direct Sow January 30 Jan 30 โ€“ Feb 20
Fall Sowing October 6 Oct 6 โ€“ Oct 20
Harvest February 27 Feb 27 โ€“ Mar 20

Plant 0.5" deep ยท 2" apart ยท Rows 6" apart

Month-by-Month Timeline

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

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

22โ€“35 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 9a

Growing Season

284 days

Growing Tips for St. John the Baptist Parish

Direct sow every 1-2 weeks for continuous harvest. Do not transplant. Harvest spring radishes promptly to prevent them from becoming pithy and hot.

Companion Planting

Good Companions

Avoid Planting Near

  • Hyssop

Level Up Your Garden

Frequently Asked Questions

When should I plant Radish in St. John the Baptist Parish, LA?

St. John the Baptist Parish is in Zone 9a with an average last frost of February 20. Plan your Radish planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is St. John the Baptist Parish, LA?

St. John the Baptist Parish, Louisiana is in USDA Hardiness Zone 9a. The average last spring frost is February 20 and first fall frost is December 1.

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Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help St. John the Baptist Parish gardeners in Zone 9a organize planting dates, track what's growing, and never miss a planting window.

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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. John the Baptist Parish, LA. Local conditions may vary. Last updated: April 2026.