When to plant Zinnia in Duval County, FL
Spring Zinnia in Duval County goes in January 27–February 17, once nighttime temps stop dipping near freezing.
When to Plant Zinnia in Duval County, FL
Your June gardening checklist
We've pulled the most time-sensitive tasks for Duval County, Florida this June and put them front and centre. Tackle them in order.
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Bring in the zinnia
Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.
A few tasks this June that'll pay off in July
- First harvests: zinnia
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.
Duval County, Florida is in USDA Zone 9b. The average last spring frost is February 24 and the first fall frost is November 29, giving you a growing season of approximately 278 days.
At an elevation of 337 feet, Duval County receives approximately 56.9 inches of rainfall annually with predominantly sand soil. Summer highs average 102°F, so Zinnia may need afternoon shade and extra watering during peak heat. 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.
Duval County Soil Profile
Soil Type
Sand
Soil pH
5-5.8
Drainage
Well Drained
Zinnia Planting Risk Windows
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 Duval County
How your county's soil matches Zinnia's growing requirements.
Soil pH
Your soil pH (5.0–5.8) is more acidic than Zinnia prefers (5.5–7.5). Add garden lime to raise pH.
Soil Texture
Sandy soil in Duval 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
Succession Planting Zinnia
Sow every 6.9 weeks. Last sowing by Sep 20 to harvest before frost.
Zinnia Water Budget
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 | — | 2.6" | 0" | ❄️ Dormant |
| Feb | 2.2" | 2.8" | 0" | ✅ Rainfall sufficient |
| Mar | 2.2" | 3.6" | 0" | ✅ Rainfall sufficient |
| Apr | 2.2" | 3" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 3.5" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 8.7" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 7.8" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 8.9" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 6.3" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 4.7" | 0" | ✅ Rainfall sufficient |
| Nov | 2.2" | 2.6" | 0" | ✅ Rainfall sufficient |
| Dec | — | 2.4" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Feb–Nov in Duval 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 Planting Timeline — Duval County, FL
Zinnia Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 27 | Jan 27 – Feb 10 |
| Transplant Outdoors | January 27 | Jan 27 – Feb 10 |
| Direct Sow | January 27 | Jan 27 – Feb 17 |
| Bloom | April 7 | Apr 7 – Oct 6 |
Plant 0.3" deep · 12" apart · Rows 18" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors Transplant Outdoors Direct Sow |
| February | Start Indoors Transplant Outdoors Direct Sow |
| March | — |
| 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: too_acidic
🗺️ USDA Zone
Zone 9b
📆 Growing Season
278 days in Duval County
Growing Tips for Zinnia in Duval County
Direct sow Zinnia outdoors after February 24 in Duval County when soil has warmed and frost danger has passed.
Sandy soil in Duval County dries quickly — mulch Zinnia with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
With summer highs reaching 102°F in Duval County, provide afternoon shade for Zinnia and water deeply in the morning.
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
Check more plant combinations with our Companion Planting Checker →
Zinnia in Other Locations
Frequently Asked Questions
When should I plant Zinnia in Duval County, FL?
Duval County is in Zone 9b with an average last frost of February 24. Plan your Zinnia planting based on this frost date — see the calendar above for exact timing.
What planting zone is Duval County, FL?
Duval County, Florida is in USDA Hardiness Zone 9b. The average last spring frost is February 24 and first fall frost is November 29.
When should I plant Zinnia in Duval County, FL?
In Duval County, FL, plant Zinnia after the last frost (around February 24) and before the first frost (around November 29). Best results when soil holds above 50°F.
What growing zone is Duval County, FL for Zinnia?
Duval County sits in USDA Zone 9b. Zinnia grows reliably in zones 3a through 11b, so it's a good fit here.
Can Zinnia grow in Duval County's climate?
Yes — Zinnia grows well in Duval County's temperate climate. Duval County averages a 279-day frost-free season, with last frost around February 24 and first frost around November 29.
Your Duval County Garden Planner — Free
A 22-page printable planner built for Duval 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.