When to plant Cosmos in Broward County County,
For Broward County County, gardeners: plant Cosmos November 6 through November 27 once soil reads 50°F.
When to Plant Cosmos in Broward County, FL
What to do in June
We've pulled the most time-sensitive tasks for Broward County, Florida this June and put them front and centre. Tackle them in order.
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Survive, don't thrive
June-August is endurance gardening. Keep okra, peppers, sweet potatoes, and southern peas alive. Harvest everything daily before the heat damages produce on the vine.
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Start fall tomato seeds indoors
Yes, indoors — under lights or in AC. They'll be ready to transplant in August when temperatures briefly moderate.
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Add compost to empty beds
Empty beds get a thick layer of compost + mulch to suppress weeds and feed the soil for fall planting.
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.
Broward County, Florida is in USDA Zone 11a. The average last spring frost is January 1 and the first fall frost is December 31, giving you a growing season of approximately 364 days.
At an elevation of 209 feet, Broward County receives approximately 60.7 inches of rainfall annually with predominantly sand soil. Summer highs average 93°F, providing good warmth for Cosmos during the growing season. Sandy soil warms quickly in spring — great for early planting — but Cosmos will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Cosmos root diseases.
Broward County Soil Profile
Soil Type
Sand
Soil pH
5.1-6
Drainage
Well Drained
Soil Compatibility in Broward County
How your county's soil matches Cosmos's growing requirements.
Soil pH
Your soil pH (5.1–6.0) is more acidic than Cosmos prefers (6.0–8.0). Add garden lime to raise pH.
Soil Texture
Sandy soil in Broward County warms quickly in spring but drains fast. Cosmos will need more frequent watering and regular compost additions to retain nutrients.
Drainage
Drainage is adequate for Cosmos.
Organic Matter
Organic matter is low (1.5%). Add 2-3 inches of compost before planting Cosmos.
How to Plant Cosmos
Cosmos Water Budget
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 | 2.2" | 3" | 0" | ✅ Rainfall sufficient |
| Feb | 2.2" | 2.8" | 0" | ✅ Rainfall sufficient |
| Mar | 2.2" | 3.3" | 0" | ✅ Rainfall sufficient |
| Apr | 2.2" | 2.5" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 4.1" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 8.7" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 10.1" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 9.1" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 7.9" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 4.7" | 0" | ✅ Rainfall sufficient |
| Nov | 2.2" | 2.1" | 0.1" | 💧 Light watering |
| Dec | 2.2" | 2.2" | 0" | ✅ Rainfall sufficient |
Water needs are for active growing months only (Jan–Dec in Broward 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 Planting Timeline — Broward County, FL
Cosmos Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | December 4 | Dec 4 – Dec 18 |
| Transplant Outdoors | November 6 | Nov 6 – Nov 20 |
| Direct Sow | November 6 | Nov 6 – Nov 27 |
| Bloom | January 15 | Jan 15 – Aug 27 |
Plant 0.3" deep · 12" apart · Rows 18" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Bloom |
| February | Bloom |
| March | Bloom |
| April | Bloom |
| May | Bloom |
| June | Bloom |
| July | Bloom |
| August | Bloom |
| September | — |
| October | — |
| November | Transplant Outdoors Direct Sow |
| December | Start Indoors |
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: too_acidic
🗺️ USDA Zone
Zone 11a
📆 Growing Season
365 days in Broward County
Growing Tips for Cosmos in Broward County
Sandy soil in Broward County dries quickly — mulch Cosmos with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
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 →
Cosmos in Other Locations
Frequently Asked Questions
When should I plant Cosmos in Broward County, FL?
Broward County is in Zone 11a with an average last frost of January 1. Plan your Cosmos planting based on this frost date — see the calendar above for exact timing.
What planting zone is Broward County, FL?
Broward County, Florida is in USDA Hardiness Zone 11a. The average last spring frost is January 1 and first fall frost is December 31.
When should I plant Cosmos in Broward County, ?
In Broward County, , plant Cosmos after the last frost (around January 1) and before the first frost (around December 31). Best results when soil holds above 50°F.
What growing zone is Broward County, for Cosmos?
Broward County sits in USDA Zone 11a. Cosmos grows reliably in zones 2a through 11b, so it's a good fit here.
Can Cosmos grow in Broward County's climate?
Yes — Cosmos grows well in Broward County's temperate climate. Broward County averages a 365-day frost-free season, with last frost around January 1 and first frost around December 31.
Your Broward County Garden Planner — Free
A 22-page printable planner built for Broward County (Zone 11a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.