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When to plant Zinnia in Kellerman, AL

Kellerman gardeners should plant Zinnia between March 8 and March 29 in spring. With Kellerman's Zone 8b climate (last frost March 22), Zinnia needs 60–70 days to mature — plant by August 31 for a full harvest.

When to Plant Zinnia in Kellerman, AL

Tuscaloosa County, Alabama Zone 8b July

Your July gardening checklist

If you only do a handful of things in the garden this July, make it these. They're sequenced around your zone's frost timing.

Avg. last frost March 22
Avg. first frost November 9
Soil temp (4") 86°F
Watering Low
Pest pressure High
Daylight 14 hrs
  1. Basket week: zinnia

    The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.

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.

Kellerman, Alabama is in USDA Zone 8b. The average last spring frost is March 22 and the first fall frost is November 9, giving you a growing season of approximately 232 days.

At an elevation of 436 feet, Tuscaloosa County receives approximately 52.9 inches of rainfall annually with predominantly clay loam soil. Summer highs average 94°F, providing good warmth for Zinnia during the growing season. Clay soil retains moisture well for Zinnia, but amend with compost to improve drainage and prevent root rot. 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
Kellerman, AL (Zone 8b) Long season
232 days
Last Spring Frost March 22
232 growing days
First Fall Frost November 9

Kellerman Soil Profile

Soil Type

Clay Loam

Soil pH

5.5-6.2

Drainage

Well Drained

Zinnia Planting Risk Windows

Early Start (70% safe) ✓ Fits season (22 days to spare)
Start indoors: Feb 13 Transplant: Feb 27 🌸 Bloom: May 8 – Oct 9
Recommended (50%) ✓ Fits season (22 days to spare)
Start indoors: Feb 22 Transplant: Mar 8 🌸 Bloom: May 17 – Oct 18
Safe Start (90%) ✓ Fits season (16 days to spare)
Start indoors: Mar 17 Transplant: Mar 31 🌸 Bloom: Jun 9 – Nov 10

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 Kellerman

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

Soil pH

Your soil pH (5.5–6.2) is within Zinnia's preferred range (5.5–7.5).

Soil Texture

The clay loam soil in Tuscaloosa County is excellent for Zinnia — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.4%). Annual compost additions will help Zinnia.

How to Plant Zinnia

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

Succession Planting Zinnia

4
successive plantings in your 232-day season

Sow every 6.9 weeks. Last sowing by Aug 31 to harvest before frost.

Zinnia Water Budget

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

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

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 4.5" 0" ❄️ Dormant
Feb 4.7" 0" ❄️ Dormant
Mar 2.2" 5.2" 0" ✅ Rainfall sufficient
Apr 2.2" 4.1" 0" ✅ Rainfall sufficient
May 2.2" 3.6" 0" ✅ Rainfall sufficient
Jun 2.2" 4.7" 0" ✅ Rainfall sufficient
Jul 2.2" 5.3" 0" ✅ Rainfall sufficient
Aug 2.2" 4.4" 0" ✅ Rainfall sufficient
Sep 2.2" 3.5" 0" ✅ Rainfall sufficient
Oct 2.2" 3.9" 0" ✅ Rainfall sufficient
Nov 2.2" 4.5" 0" ✅ Rainfall sufficient
Dec 4.6" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Tuscaloosa 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 ~1,332 GDD — county provides 4,756 GDD Excellent fit

Zinnia Planting Timeline — Kellerman, AL

Zinnia Planting Calendar

Activity When Date Range
Start Indoors February 22 Feb 22 – Mar 8
Transplant Outdoors March 8 Mar 8 – Mar 22
Direct Sow March 8 Mar 8 – Mar 29
Bloom May 17 May 17 – Oct 18

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

Month-by-Month Timeline

MonthActivities
January
February Start Indoors
March Start Indoors Transplant Outdoors Direct Sow
April
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: ideal

🗺️ USDA Zone

Zone 8b

📆 Growing Season

232 days in Tuscaloosa County

Growing Tips for Zinnia in Kellerman

Direct sow Zinnia outdoors after March 22 in Tuscaloosa County when soil has warmed and frost danger has passed.

With Tuscaloosa County's clay soil (33% clay), work in 3-4 inches of compost before planting Zinnia. Avoid tilling when soil is wet to prevent compaction.

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 →

When should I plant Zinnia in Kellerman, AL?

In Kellerman, AL, plant Zinnia after the last frost (around March 22) and before the first frost (around November 9). Best results when soil holds above 50°F.

What growing zone is Kellerman, AL for Zinnia?

Kellerman sits in USDA Zone 8b. Zinnia grows reliably in zones 3a through 11b, so it's a good fit here.

Can Zinnia grow in Kellerman's climate?

Yes — Zinnia grows well in Kellerman's temperate climate. Kellerman averages a 232-day frost-free season, with last frost around March 22 and first frost around November 9.

🌱

Your Tuscaloosa County Garden Planner — Free

A 22-page printable planner built for Tuscaloosa County (Zone 8b). 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 Tuscaloosa County, AL. Local conditions may vary. Last updated: July 2026.