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When to plant Tomatillo in St. Helena Parish County,

St. Helena Parish County's climate puts the Tomatillo spring window between March 5 and March 26. aim for a steady week of warm soil before planting.

When to Plant Tomatillo in St. Helena Parish, LA

St. Helena Parish, Louisiana Zone 9a June

What to do in June

If you only do a handful of things in the garden this June, make it these. They're sequenced around your zone's frost timing.

Avg. last frost March 5
Avg. first frost November 30
Soil temp (4") 84°F
Watering Low
Pest pressure High
Daylight 14 hrs
  1. Basket week: tomatillo

    If you can't use it all right away, check the food-preservation section of your planner.

Looking ahead to July
  • First harvests: tomatillo

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Tomatillos are a Mexican staple that produces tart, green fruits enclosed in papery husks. They are essential for salsa verde and green sauces.

St. Helena Parish, Louisiana is in USDA Zone 9a. 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 96°F, so Tomatillo may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Tomatillo will need more frequent watering and organic matter to retain nutrients.

St. Helena Parish, LA (Zone 9a) Year-round
270 days
Last Spring Frost March 5
270 growing days
First Fall Frost November 30
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St. Helena Parish Soil Profile

Soil Type

Sandy Loam

Soil pH

4.8-6.5

Drainage

Well Drained

Tomatillo Planting Risk Windows

Early Start (70% safe) ✓ Fits season (138 days to spare)
Start indoors: Jan 4 Transplant: Feb 22 🍅 Harvest: Apr 26 – Jul 5
Recommended (50%) ✓ Fits season (130 days to spare)
Start indoors: Jan 22 Transplant: Mar 12 🍅 Harvest: May 14 – Jul 23
Safe Start (90%) ✓ Fits season (124 days to spare)
Start indoors: Feb 12 Transplant: Apr 2 🍅 Harvest: Jun 4 – Aug 13

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 St. Helena Parish

How your county's soil matches Tomatillo's growing requirements.

Soil pH

Your soil pH (4.8–6.5) is more acidic than Tomatillo prefers (6.0–7.0). Add garden lime to raise pH.

Soil Texture

Sandy soil in St. Helena Parish warms quickly in spring but drains fast. Tomatillo will need more frequent watering and regular compost additions to retain nutrients.

Organic Matter

Organic matter is low (1.7%). Add 2-3 inches of compost before planting Tomatillo.

How to Plant Tomatillo

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Succession Planting Tomatillo

5
successive plantings in your 270-day season

Sow every 6.9 weeks. Last sowing by Sep 06 to harvest before frost.

Tomatillo Water Budget

Plant needs
1.1″/week
Rainfall provides
0.8″/week
You supply
0.3″/week
Watering frequency 1-2 times/week
Season total 774 gal / 100 sq ft

Monthly Watering Guide for Tomatillo

Tomatillo needs approximately 1.1 inches of water per week (4.8" per month). Here's how your county's rainfall compares month by month.

Month Tomatillo Needs Rainfall You Supplement Action
Jan 3.8" 0" ❄️ Dormant
Feb 3.7" 0" ❄️ Dormant
Mar 4.8" 5.5" 0" ✅ Rainfall sufficient
Apr 4.8" 3.3" 1.5" 💧 Light watering
May 4.8" 3.6" 1.2" 💧 Light watering
Jun 4.8" 4.9" 0" ✅ Rainfall sufficient
Jul 4.8" 4.7" 0.1" 💧 Light watering
Aug 4.8" 5.1" 0" ✅ Rainfall sufficient
Sep 4.8" 3.6" 1.2" 💧 Light watering
Oct 4.8" 3.3" 1.5" 💧 Light watering
Nov 4.8" 4.4" 0.4" 💧 Light watering
Dec 4" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in St. Helena Parish). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Tomatillo 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" — every day above 50°F 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.

Tomatillo needs ~1,595 GDD — county provides 5,940 GDD Excellent fit

Tomatillo Planting Timeline — St. Helena Parish, LA

Tomatillo Planting Calendar

Activity When Date Range
Start Indoors January 22 Jan 22 – Feb 5
Transplant Outdoors March 12 Mar 12 – Mar 26
Direct Sow March 5 Mar 5 – Mar 26
Harvest May 14 May 14 – Jul 23

Plant 1" deep · 15" apart · Rows 24" apart

Month-by-Month Timeline

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

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1.1"/week · 1-2 times/week

📅 Days to Maturity

60–85 days

🧪 Soil pH

Needs 6–7 · Your soil: too_acidic

🗺️ USDA Zone

Zone 9a

📆 Growing Season

270 days in St. Helena Parish

Growing Tips for Tomatillo in St. Helena Parish

Direct sow Tomatillo outdoors after March 05 in St. Helena Parish when soil has warmed and frost danger has passed.

Sandy soil in St. Helena Parish dries quickly — mulch Tomatillo with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

With summer highs reaching 96°F in St. Helena Parish, provide afternoon shade for Tomatillo and water deeply in the morning.

Common pests for Tomatillo in this region include tomato hornworm and aphids. Use row covers early in the season and inspect plants weekly.

General growing tips

Start seeds indoors 6-8 weeks before last frost. Plant at least two plants for cross-pollination. Harvest when fruits fill the husk and it begins to split.

Companion Planting

Good Companions

Avoid Planting Near

  • Fennel
  • Dill

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

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

St. Helena Parish is in Zone 9a with an average last frost of March 5. Plan your Tomatillo planting based on this frost date — see the calendar above for exact timing.

What planting zone is St. Helena Parish, LA?

St. Helena Parish, Louisiana is in USDA Hardiness Zone 9a. The average last spring frost is March 5 and first fall frost is November 30.

When should I plant Tomatillo in St. Helena Parish County, ?

In St. Helena Parish County, , plant Tomatillo after the last frost (around March 5) and before the first frost (around November 30). Best results when soil holds above 50°F.

What growing zone is St. Helena Parish County, for Tomatillo?

St. Helena Parish County sits in USDA Zone 9a. Tomatillo grows reliably in zones 4a through 11b, so it's a good fit here.

Can Tomatillo grow in St. Helena Parish County's climate?

Yes — Tomatillo grows well in St. Helena Parish County's temperate climate. St. Helena Parish County averages a 270-day frost-free season, with last frost around March 5 and first frost around November 30.

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Your St. Helena Parish Garden Planner — Free

A 22-page printable planner built for St. Helena Parish (Zone 9a). 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. Helena Parish, LA. Local conditions may vary. Last updated: June 2026.

Sources & credits

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