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When to plant Zinnia in Suwannee County, FL

Suwannee County's spring Zinnia window runs February 11 through March 4. aim for a steady week of warm soil before planting.

When to Plant Zinnia in Suwannee County, FL

Suwannee County, Florida Zone 9a July

What to do in July

Each item below is timed to Suwannee County, Florida's frost dates and soil temperatures. Skip nothing, stress about nothing.

Avg. last frost March 4
Avg. first frost November 26
Soil temp (4") 91°F
Watering Low
Pest pressure High
Daylight 13.8 hrs
  1. Bring in the zinnia

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

To set up a strong August, finish these tasks
  • First harvests: zinnia

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Zinnia (Zinnia elegans) is a fast-growing, heat-loving annual that produces bold, dahlia-like blooms from early summer until hard frost. One of the easiest flowers to grow from direct-sown seed, zinnias thrive in hot, dry conditions and are magnets for butterflies and beneficial insects. They make excellent companion plants alongside marigolds in the vegetable garden.

Suwannee County, Florida is in USDA Zone 9a. The average last spring frost is March 4 and the first fall frost is November 26, giving you a growing season of approximately 267 days.

At an elevation of 383 feet, Suwannee County receives approximately 53.6 inches of rainfall annually with predominantly sand soil. Summer highs average 91°F, providing good warmth for Zinnia during the growing season. Sandy soil warms quickly in spring — great for early planting — but Zinnia will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Zinnia root diseases.

Annual Blooms in Summer Pollinator-friendly Deer-resistant Good for cutting
Suwannee County, FL (Zone 9a) Long season
267 days
Last Spring Frost March 4
267 growing days
First Fall Frost November 26

Suwannee County Soil Profile

Soil Type

Sand

Soil pH

5.1-6

Drainage

Well Drained

Zinnia Planting Risk Windows

Early Start (70% safe) ✓ Fits season (53 days to spare)
Start indoors: Jan 22 Transplant: Jan 29 🌸 Bloom: Apr 9 – Sep 24
Recommended (50%) ✓ Fits season (50 days to spare)
Start indoors: Feb 4 Transplant: Feb 11 🌸 Bloom: Apr 22 – Oct 7
Safe Start (90%) ✓ Fits season (54 days to spare)
Start indoors: Feb 24 Transplant: Mar 3 🌸 Bloom: May 12 – Oct 27

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 Suwannee County

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

Soil pH

Your soil pH (5.1–6.0) overlaps with Zinnia's range (5.5–7.5), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is low (1.4%). Add 2-3 inches of compost before planting Zinnia.

How to Plant Zinnia

0.3"
Planting Depth
12"
Between Plants
18"
Between Rows

Succession Planting Zinnia

5
successive plantings in your 267-day season

Sow every 6.9 weeks. Last sowing by Sep 17 to harvest before frost.

Zinnia Water Budget

Plant needs
0.5″/week
Rainfall provides
0.8″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Zinnia

Zinnia needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.

Month Zinnia Needs Rainfall You Supplement Action
Jan 2.5" 0" ❄️ Dormant
Feb 3" 0" ❄️ Dormant
Mar 2.2" 3.2" 0" ✅ Rainfall sufficient
Apr 2.2" 2.6" 0" ✅ Rainfall sufficient
May 2.2" 3.8" 0" ✅ Rainfall sufficient
Jun 2.2" 8" 0" ✅ Rainfall sufficient
Jul 2.2" 7.8" 0" ✅ Rainfall sufficient
Aug 2.2" 7.3" 0" ✅ Rainfall sufficient
Sep 2.2" 7.1" 0" ✅ Rainfall sufficient
Oct 2.2" 4.1" 0" ✅ Rainfall sufficient
Nov 2.2" 2.3" 0" ✅ Rainfall sufficient
Dec 2" 0" ❄️ Dormant

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

Zinnia 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.

Zinnia needs ~1,186 GDD — county provides 4,872 GDD Excellent fit

Zinnia Planting Timeline — Suwannee County, FL

Zinnia Planting Calendar

Activity When Date Range
Start Indoors February 4 Feb 4 – Feb 18
Transplant Outdoors February 11 Feb 11 – Feb 25
Direct Sow February 11 Feb 11 – Mar 4
Bloom April 22 Apr 22 – Oct 7

Plant 0.3" deep · 12" apart · Rows 18" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

60–70 days

🧪 Soil pH

Needs 5.5–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 9a

📆 Growing Season

267 days in Suwannee County

Growing Tips for Zinnia in Suwannee County

Direct sow Zinnia outdoors after March 04 in Suwannee County when soil has warmed and frost danger has passed.

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

Common pests for Zinnia in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.

General growing tips

Direct-sow after last frost when soil reaches 60°F; seeds germinate in 5-7 days. In zones 3-5 a brief indoor start (4 weeks) is worthwhile but transplant carefully — zinnias dislike root disturbance. Deadhead frequently to extend bloom. Excellent cut flower; harvesting regularly encourages branching. Avoid overhead watering to reduce powdery mildew.

Companion Planting

Good Companions

Avoid Planting Near

  • Fennel

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Zinnia in Suwannee County, FL?

Suwannee County is in Zone 9a with an average last frost of March 4. Plan your Zinnia planting based on this frost date — see the calendar above for exact timing.

What planting zone is Suwannee County, FL?

Suwannee County, Florida is in USDA Hardiness Zone 9a. The average last spring frost is March 4 and first fall frost is November 26.

When should I plant Zinnia in Suwannee County, FL?

In Suwannee County, FL, plant Zinnia after the last frost (around March 4) and before the first frost (around November 26). Best results when soil holds above 50°F.

What growing zone is Suwannee County, FL for Zinnia?

Suwannee County sits in USDA Zone 9a. Zinnia grows reliably in zones 3a through 11b, so it's a good fit here.

Can Zinnia grow in Suwannee County's climate?

Yes — Zinnia grows well in Suwannee County's temperate climate. Suwannee County averages a 267-day frost-free season, with last frost around March 4 and first frost around November 26.

🌱

Your Suwannee County Garden Planner — Free

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

Sources & credits

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