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When to plant Cosmos in Dade County County,

Plant Cosmos in Dade County County, when soil hits 50°F — usually March 25. Continue planting through April 15 for the spring crop.

When to Plant Cosmos in Dade County, GA

Dade County, Georgia Zone 7b June

June to-do list for Dade County, Georgia

Your Dade County, Georgia garden is entering a new phase. Here's what's on the schedule for June and why each task matters now.

Avg. last frost April 1
Avg. first frost October 31
Soil temp (4") 78°F
Watering Low
Pest pressure High
Daylight 14.3 hrs
  1. Start harvesting cosmos

    Morning harvests are best — cooler temperatures mean crisper produce and longer fridge life.

July will be here before you know it — start on
  • First harvests: cosmos

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Cosmos (Cosmos bipinnatus) is an airy, feathery-foliaged cottage garden annual from Mexico that thrives on neglect. It produces delicate daisy-like blooms in shades of pink, white, and magenta from midsummer until frost. Cosmos is a prolific self-sower — once established in a garden it often returns year after year without replanting. Excellent habitat plant for beneficial insects.

Dade County, Georgia is in USDA Zone 7b. The average last spring frost is April 1 and the first fall frost is October 31, giving you a growing season of approximately 213 days.

At an elevation of 77 feet, Dade County receives approximately 60.9 inches of rainfall annually with predominantly clay loam soil. Summer highs average 89°F, providing good warmth for Cosmos during the growing season. Clay soil retains moisture well for Cosmos, but amend with compost to improve drainage and prevent root rot. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Cosmos root diseases.

Annual Blooms in Summer Pollinator-friendly Good for cutting
Dade County, GA (Zone 7b) Long season
213 days
Last Spring Frost April 1
213 growing days
First Fall Frost October 31

Dade County Soil Profile

Soil Type

Clay Loam

Soil pH

5.7-6.7

Drainage

Well Drained

Cosmos Planting Risk Windows

Early Start (70% safe) ✓ Fits season (23 days to spare)
Start indoors: Feb 26 Transplant: Mar 19 🌸 Bloom: May 28 – Oct 1
Recommended (50%) ✓ Fits season (24 days to spare)
Start indoors: Mar 4 Transplant: Mar 25 🌸 Bloom: Jun 3 – Oct 7
Safe Start (90%) ✓ Fits season (21 days to spare)
Start indoors: Mar 21 Transplant: Apr 11 🌸 Bloom: Jun 20 – Oct 24

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 Dade County

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

Soil pH

Your soil pH (5.7–6.7) overlaps with Cosmos's range (6.0–8.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.3%). Annual compost additions will help Cosmos.

How to Plant Cosmos

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

Succession Planting Cosmos

4
successive plantings in your 213-day season

Sow every 6.9 weeks. Last sowing by Aug 02 to harvest before frost.

Cosmos Water Budget

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

Monthly Watering Guide for Cosmos

Cosmos 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 Cosmos Needs Rainfall You Supplement Action
Jan 5.5" 0" ❄️ Dormant
Feb 5.2" 0" ❄️ Dormant
Mar 6.5" 0" ❄️ Dormant
Apr 2.2" 4.7" 0" ✅ Rainfall sufficient
May 2.2" 4.5" 0" ✅ Rainfall sufficient
Jun 2.2" 5.4" 0" ✅ Rainfall sufficient
Jul 2.2" 5.7" 0" ✅ Rainfall sufficient
Aug 2.2" 5.4" 0" ✅ Rainfall sufficient
Sep 2.2" 4.2" 0" ✅ Rainfall sufficient
Oct 2.2" 3.8" 0" ✅ Rainfall sufficient
Nov 4.6" 0" ❄️ Dormant
Dec 5.4" 0" ❄️ Dormant

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

Cosmos 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.

Cosmos needs ~1,256 GDD — county provides 3,567 GDD Excellent fit

Cosmos Planting Timeline — Dade County, GA

Cosmos Planting Calendar

Activity When Date Range
Start Indoors March 4 Mar 4 – Mar 18
Transplant Outdoors March 25 Mar 25 – Apr 8
Direct Sow March 25 Mar 25 – Apr 15
Bloom June 3 Jun 3 – Oct 7

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

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors Transplant Outdoors Direct Sow
April Transplant Outdoors Direct Sow
May
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

60–90 days

🧪 Soil pH

Needs 6–8 · Your soil: acceptable

🗺️ USDA Zone

Zone 7b

📆 Growing Season

213 days in Dade County

Growing Tips for Cosmos in Dade County

Direct sow Cosmos outdoors after April 01 in Dade County when soil has warmed and frost danger has passed.

With Dade County's clay soil (32% clay), work in 3-4 inches of compost before planting Cosmos. Avoid tilling when soil is wet to prevent compaction.

Common pests for Cosmos 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; cosmos germinates readily at 65-80°F in 7-10 days. Avoid rich soil — excess fertility produces lush foliage at the expense of blooms. Cosmos tolerates poor, dry soil exceptionally well. Pinch seedlings at 8 inches to encourage branching. Self-sows freely; allow some seed heads to mature and drop for a no-fuss perennial effect in warm climates.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Cosmos in Dade County, GA?

Dade County is in Zone 7b with an average last frost of April 1. Plan your Cosmos planting based on this frost date — see the calendar above for exact timing.

What planting zone is Dade County, GA?

Dade County, Georgia is in USDA Hardiness Zone 7b. The average last spring frost is April 1 and first fall frost is October 31.

When should I plant Cosmos in Dade County, ?

In Dade County, , plant Cosmos after the last frost (around April 1) and before the first frost (around October 31). Best results when soil holds above 50°F.

What growing zone is Dade County, for Cosmos?

Dade County sits in USDA Zone 7b. Cosmos grows reliably in zones 2a through 11b, so it's a good fit here.

Can Cosmos grow in Dade County's climate?

Yes — Cosmos grows well in Dade County's temperate climate. Dade County averages a 213-day frost-free season, with last frost around April 1 and first frost around October 31.

🌱

Your Dade County Garden Planner — Free

A 22-page printable planner built for Dade County (Zone 7b). 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 Dade County, GA. 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.