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When to plant Petunia in Putnam County County,

Plant Petunia in Putnam County County during the brief January 19–February 2 window. With 297 frost-free days, fall plantings can't mature before December 2.

When to Plant Petunia in Putnam County, FL

Putnam County, Florida Zone 9b June

Your June gardening checklist

June rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Putnam County, Florida.

Avg. last frost February 9
Avg. first frost December 2
Soil temp (4") 87°F
Watering Low
Pest pressure High
Daylight 13.9 hrs
  1. Harvest petunia as they ripen

    This is the payoff month. Bring a basket, bring a friend, and get into the beds.

Coming up in July — start thinking about
  • 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.

Putnam County, Florida is in USDA Zone 9b. The average last spring frost is February 9 and the first fall frost is December 2, giving you a growing season of approximately 296 days.

At an elevation of 278 feet, Putnam County receives approximately 57.5 inches of rainfall annually with predominantly sand soil. Summer highs average 95°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
Putnam County, FL (Zone 9b) Year-round
296 days
Last Spring Frost February 9
296 growing days
First Fall Frost December 2
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Putnam County Soil Profile

Soil Type

Sand

Soil pH

4.9-6.2

Drainage

Well Drained

Petunia Planting Risk Windows

Early Start (70% safe) ✓ Fits season (87 days to spare)
Start indoors: Nov 30 Transplant: Jan 4 🌸 Bloom: Mar 15 – Aug 30
Recommended (50%) ✓ Fits season (79 days to spare)
Start indoors: Dec 15 Transplant: Jan 19 🌸 Bloom: Mar 30 – Sep 14
Safe Start (90%) ✓ Fits season (80 days to spare)
Start indoors: Jan 7 Transplant: Feb 11 🌸 Bloom: Apr 22 – Oct 7

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 Putnam County

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

Soil pH

Your soil pH (4.9–6.2) is more acidic than Petunia prefers (6.0–7.0). Add garden lime to raise pH.

Soil Texture

Sandy soil in Putnam 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 (1.4%). Add 2-3 inches of compost before planting Petunia.

How to Plant Petunia

12"
Between Plants
12"
Between Rows

Succession Planting Petunia

5
successive plantings in your 296-day season

Sow every 8 weeks. Last sowing by Sep 03 to harvest before frost.

Petunia Water Budget

Plant needs
1.0″/week
Rainfall provides
0.8″/week
You supply
0.6″/week
Watering frequency 1-2 times/week
Season total 1,544 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

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 2.4" 0" ❄️ Dormant
Feb 4.3" 2.6" 1.7" 💧 Light watering
Mar 4.3" 3.5" 0.8" 💧 Light watering
Apr 4.3" 2.3" 2" 💧 Light watering
May 4.3" 3.3" 1" 💧 Light watering
Jun 4.3" 7.9" 0" ✅ Rainfall sufficient
Jul 4.3" 9.4" 0" ✅ Rainfall sufficient
Aug 4.3" 8.7" 0" ✅ Rainfall sufficient
Sep 4.3" 7.4" 0" ✅ Rainfall sufficient
Oct 4.3" 5.3" 0" ✅ Rainfall sufficient
Nov 4.3" 2.2" 2.1" 💧 Light watering
Dec 4.3" 2.6" 1.7" 💧 Light watering

Water needs are for active growing months only (Feb–Dec in Putnam 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 ~1,700 GDD — county provides 6,311 GDD Excellent fit

Petunia Planting Timeline — Putnam County, FL

Petunia Planting Calendar

Activity When Date Range
Start Indoors December 15 Dec 15 – Dec 29
Transplant Outdoors January 19 Jan 19 – Feb 2
Bloom March 30 Mar 30 – Sep 14

· 12" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January Transplant Outdoors
February Transplant Outdoors
March Bloom
April Bloom
May Bloom
June Bloom
July Bloom
August Bloom
September Bloom
October
November
December Start Indoors
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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 9b

📆 Growing Season

296 days in Putnam County

Growing Tips for Petunia in Putnam County

Direct sow Petunia outdoors after February 09 in Putnam County when soil has warmed and frost danger has passed.

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

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 Putnam County, FL?

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

What planting zone is Putnam County, FL?

Putnam County, Florida is in USDA Hardiness Zone 9b. The average last spring frost is February 9 and first fall frost is December 2.

When should I plant Petunia in Putnam County, ?

In Putnam County, , plant Petunia after the last frost (around February 9) and before the first frost (around December 2). Best results when soil holds above 50°F.

What growing zone is Putnam County, for Petunia?

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

Can Petunia grow in Putnam County's climate?

Yes — Petunia grows well in Putnam County's temperate climate. Putnam County averages a 297-day frost-free season, with last frost around February 9 and first frost around December 2.

🌱

Your Putnam County Garden Planner — Free

A 22-page printable planner built for Putnam County (Zone 9b). 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 Putnam County, FL. 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.