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When to plant Petunia in Clay County County,

In Clay County County, Petunia is a spring-only crop. Plant February 4–February 18 once soil hits 50°F.

When to Plant Petunia in Clay County, FL

Clay County, Florida Zone 9a June

Your June gardening checklist

Your garden in Clay County, Florida is working on a schedule, even when you're not. Here's where you should be this June.

Avg. last frost February 18
Avg. first frost November 27
Soil temp (4") 88°F
Watering Low
Pest pressure High
Daylight 13.9 hrs
  1. Collect petunia at their peak

    Check every 1–2 days. Many of these get tough or go to seed if you wait too long.

July prep starts now
  • First harvests: petunia

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Petunias (Petunia x hybrida) are warm-season tender annuals prized for their prolific, trumpet-shaped blooms in nearly every color. They perform from hanging baskets to garden borders and bloom continuously from late spring until frost, provided spent flowers are removed regularly.

Clay County, Florida is in USDA Zone 9a. The average last spring frost is February 18 and the first fall frost is November 27, giving you a growing season of approximately 282 days.

At an elevation of 122 feet, Clay County receives approximately 54.3 inches of rainfall annually with predominantly sand soil. Summer highs average 99°F, so Petunia may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Petunia will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Petunia root diseases.

Annual Blooms in Summer Pollinator-friendly Fragrant
Clay County, FL (Zone 9a) Year-round
282 days
Last Spring Frost February 18
282 growing days
First Fall Frost November 27

Clay County Soil Profile

Soil Type

Sand

Soil pH

5-5.8

Drainage

Well Drained

Petunia Planting Risk Windows

Early Start (70% safe) ✓ Fits season (71 days to spare)
Start indoors: Dec 15 Transplant: Jan 26 🌸 Bloom: Apr 6 – Sep 7
Recommended (50%) ✓ Fits season (72 days to spare)
Start indoors: Dec 24 Transplant: Feb 4 🌸 Bloom: Apr 15 – Sep 16
Safe Start (90%) ✓ Fits season (63 days to spare)
Start indoors: Jan 25 Transplant: Mar 8 🌸 Bloom: May 17 – Oct 18

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 Clay County

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

Soil pH

Your soil pH (5.0–5.8) is more acidic than Petunia prefers (6.0–7.0). Add garden lime to raise pH.

Soil Texture

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

Drainage

Drainage is adequate for Petunia.

Organic Matter

Organic matter is low (1.6%). Add 2-3 inches of compost before planting Petunia.

How to Plant Petunia

12"
Between Plants
12"
Between Rows

Succession Planting Petunia

4
successive plantings in your 282-day season

Sow every 8 weeks. Last sowing by Aug 29 to harvest before frost.

Petunia Water Budget

Plant needs
1.0″/week
Rainfall provides
0.8″/week
You supply
0.5″/week
Watering frequency 1-2 times/week
Season total 1,245 gal / 100 sq ft

Monthly Watering Guide for Petunia

Petunia needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Petunia Needs Rainfall You Supplement Action
Jan 2.6" 0" ❄️ Dormant
Feb 4.3" 3" 1.3" 💧 Light watering
Mar 4.3" 3.1" 1.2" 💧 Light watering
Apr 4.3" 2.5" 1.8" 💧 Light watering
May 4.3" 4" 0.3" 💧 Light watering
Jun 4.3" 8.5" 0" ✅ Rainfall sufficient
Jul 4.3" 7.4" 0" ✅ Rainfall sufficient
Aug 4.3" 7.4" 0" ✅ Rainfall sufficient
Sep 4.3" 6.6" 0" ✅ Rainfall sufficient
Oct 4.3" 5.1" 0" ✅ Rainfall sufficient
Nov 4.3" 2.1" 2.2" 🚿 Regular watering
Dec 2.2" 0" ❄️ Dormant

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

Petunia 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.

Petunia needs ~1,940 GDD — county provides 6,862 GDD Excellent fit

Petunia Planting Timeline — Clay County, FL

Petunia Planting Calendar

Activity When Date Range
Start Indoors December 24 Dec 24 – Jan 7
Transplant Outdoors February 4 Feb 4 – Feb 18
Bloom April 15 Apr 15 – Sep 16

· 12" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January Start Indoors
February Transplant Outdoors
March
April Bloom
May Bloom
June Bloom
July Bloom
August Bloom
September Bloom
October
November
December Start Indoors

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · 1-2 times/week

📅 Days to Maturity

70–90 days

🧪 Soil pH

Needs 6–7 · Your soil: too_acidic

🗺️ USDA Zone

Zone 9a

📆 Growing Season

282 days in Clay County

Growing Tips for Petunia in Clay County

Direct sow Petunia outdoors after February 18 in Clay County when soil has warmed and frost danger has passed.

Sandy soil in Clay County dries quickly — mulch Petunia with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

With summer highs reaching 99°F in Clay County, provide afternoon shade for Petunia and water deeply in the morning.

Common pests for Petunia 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 8–10 weeks before last frost; seeds need light to germinate — press onto moist mix surface, do not cover. Transplant after last frost once nights stay above 50°F. Pinch back leggy plants mid-summer to encourage bushy re-bloom. Wave/spreading types tolerate light shade but bloom less. Feed every 2 weeks with balanced fertilizer once established.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Petunia in Clay County, FL?

Clay County is in Zone 9a with an average last frost of February 18. Plan your Petunia planting based on this frost date — see the calendar above for exact timing.

What planting zone is Clay County, FL?

Clay County, Florida is in USDA Hardiness Zone 9a. The average last spring frost is February 18 and first fall frost is November 27.

When should I plant Petunia in Clay County, ?

In Clay County, , plant Petunia after the last frost (around February 18) and before the first frost (around November 27). Best results when soil holds above 50°F.

What growing zone is Clay County, for Petunia?

Clay County sits in USDA Zone 9a. Petunia grows reliably in zones 2a through 11b, so it's a good fit here.

Can Petunia grow in Clay County's climate?

Yes — Petunia grows well in Clay County's temperate climate. Clay County averages a 283-day frost-free season, with last frost around February 18 and first frost around November 27.

🌱

Your Clay County Garden Planner — Free

A 22-page printable planner built for Clay County (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 Clay County, FL. Local conditions may vary. Last updated: June 2026.

Sources & credits

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