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When to Plant Basil in Collier County, FL

Basil is a fragrant warm-season herb essential to Italian and Thai cuisines. It comes in many varieties including sweet, Thai, purple, and lemon types.

Collier County, Florida is in USDA Zone 10a. The average last spring frost is January 12 and the first fall frost is April 15, giving you a growing season of approximately 93 days.

At an elevation of 185 feet, Collier County receives approximately 61.3 inches of rainfall annually with predominantly sand soil. Summer highs average 85ยฐF, providing good warmth for Basil during the growing season. Sandy soil warms quickly in spring โ€” great for early planting โ€” but Basil will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Basil root diseases.

Collier County, FL (Zone 10a) Very short season
93 days
Last Spring Frost January 12
93 growing days
First Fall Frost April 15

Collier County Soil Profile

Soil Type

Sand

Soil pH

5-6.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (157 days to spare)
Start indoors: Nov 24 Transplant: Jan 12 🍅 Harvest: Mar 9 – May 11
Recommended (50%) ✓ Fits season (150 days to spare)
Start indoors: Dec 1 Transplant: Jan 19 🍅 Harvest: Mar 16 – May 18
Safe Start (90%) ✓ Fits season (122 days to spare)
Start indoors: Dec 29 Transplant: Feb 16 🍅 Harvest: Apr 13 – Jun 15

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 Collier County

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

Soil pH

Your soil pH (5.0โ€“6.2) is more acidic than Basil prefers (6.0โ€“7.0). Add garden lime to raise pH.

Soil Texture

Sandy soil in Collier County warms quickly in spring but drains fast. Basil will need more frequent watering and regular compost additions to retain nutrients.

Drainage

Drainage is adequate for Basil.

Organic Matter

Organic matter is low (1.3%). Add 2-3 inches of compost before planting Basil.

How to Plant Basil

0.5"
Planting Depth
8"
Between Plants
12"
Between Rows

Plant Water Budget

Plant needs
0.6″/week
Rainfall provides
0.7″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 242 gal / 100 sq ft

Monthly Watering Guide for Basil

Basil needs approximately 0.6 inches of water per week (2.6" per month). Here's how your county's rainfall compares month by month.

Month Basil Needs Rainfall You Supplement Action
Jan 2.6" 2.8" 0" โœ… Rainfall sufficient
Feb 2.6" 3.3" 0" โœ… Rainfall sufficient
Mar 2.6" 4.1" 0" โœ… Rainfall sufficient
Apr 2.6" 2.4" 0.2" ๐Ÿ’ง Light watering
May 2.6" 3.7" 0" โœ… Rainfall sufficient
Jun 2.6" 7.5" 0" โœ… Rainfall sufficient
Jul 2.6" 10" 0" โœ… Rainfall sufficient
Aug 2.6" 9" 0" โœ… Rainfall sufficient
Sep 2.6" 8.4" 0" โœ… Rainfall sufficient
Oct 2.6" 5.6" 0" โœ… Rainfall sufficient
Nov โ€” 2.3" 0" โ„๏ธ Dormant
Dec โ€” 2.2" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Janโ€“Oct in Collier County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Basil 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" โ€” every day above 50ยฐF 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.

Basil needs ~859 GDD — county provides 5,018 GDD Excellent fit

Basil Planting Timeline โ€” Collier County, FL

Basil Planting Calendar

Activity When Date Range
Start Indoors December 1 Dec 1 โ€“ Dec 15
Transplant Outdoors January 19 Jan 19 โ€“ Feb 2
Direct Sow January 19 Jan 19 โ€“ Feb 9
Harvest March 16 Mar 16 โ€“ May 18

Plant 0.5" deep ยท 8" apart ยท Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.6"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

50โ€“75 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 10a

๐Ÿ“† Growing Season

93 days in Collier County

Growing Tips for Basil in Collier County

Direct sow Basil outdoors after January 12 in Collier County when soil has warmed and frost danger has passed.

Sandy soil in Collier County dries quickly โ€” mulch Basil with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

General growing tips

Start seeds indoors or direct sow after last frost. Pinch flower buds to extend leaf production. Harvest leaves from the top down, cutting just above a leaf pair.

Recommended Basil Varieties for Collier County

Downy mildew-resistant basil for your humid climate

Prospera (DM-resistant) Amazel Eleonora

Companion Planting

Good Companions

Avoid Planting Near

  • Rue
  • Sage

Check more plant combinations with our Companion Planting Checker →

๐ŸŒพ Save Your Own Basil Seeds
Life Cycle Annual
Pollination Self-Pollinating
How to Collect Let flower spikes dry brown on the plant.
Storage Store airtight; viable 5 years at 35ยฐF, under 45% humidity.

Isolate 150 ft between varieties. Different basil species can cross.

Frequently Asked Questions

When should I plant Basil in Collier County, FL?

Collier County is in Zone 10a with an average last frost of January 12. Plan your Basil planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Collier County, FL?

Collier County, Florida is in USDA Hardiness Zone 10a. The average last spring frost is January 12 and first fall frost is .

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Collier County gardeners in Zone 10a 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 Collier County, FL. Local conditions may vary. Last updated: April 2026.