When to plant Broccoli in Key Biscayne, FL
In Key Biscayne, plant Broccoli in spring between December 11 and January 1, once soil temps hold above 50°F. Key Biscayne's last frost averages January 1, so aim for a steady week of warm soil before planting. For a fall crop, sow between November 5 and November 19 — roughly 60–90 days before the first frost on December 31.
When to Plant Broccoli in Key Biscayne, FL
Your July game plan for Miami-Dade County, Florida
Each item below is timed to Miami-Dade County, Florida's frost dates and soil temperatures. Skip nothing, stress about nothing.
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Plan the fall garden
Make a planting map for August. Tomatoes, peppers, brassicas, lettuce, root crops all go in over the next 8 weeks. Soil amendments and irrigation prep happen now.
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Keep heat-survivor crops productive
Daily harvest of okra and southern peas keeps plants producing. Let pods over-mature and the plant stops setting new fruit.
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Watch for hurricane prep season
August-October is hurricane season. Stake young trees, secure rain barrels, and plan how to protect tender transplants from high winds.
Broccoli is a nutrient-dense cool-season crop that produces large central heads followed by smaller side shoots. It is one of the most popular garden vegetables.
Key Biscayne, 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 123 feet, Miami-Dade County receives approximately 58.7 inches of rainfall annually with predominantly sand soil. Summer highs average 90°F, providing good warmth for Broccoli during the growing season. Sandy soil warms quickly in spring — great for early planting — but Broccoli will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Broccoli root diseases.
Key Biscayne Soil Profile
Soil Type
Sand
Soil pH
5.1-6.3
Drainage
Well Drained
Soil Compatibility in Key Biscayne
How your county's soil matches Broccoli's growing requirements.
Soil pH
Your soil pH (5.1–6.3) is more acidic than Broccoli prefers (6.0–7.0). Add garden lime to raise pH.
Soil Texture
Sandy soil in Miami-Dade County warms quickly in spring but drains fast. Broccoli will need more frequent watering and regular compost additions to retain nutrients.
Drainage
Drainage is adequate for Broccoli.
Organic Matter
Organic matter is low (1.3%). Add 2-3 inches of compost before planting Broccoli.
How to Plant Broccoli
Fall planting: Sow 8 weeks before your first frost date for a fall harvest.
How Much Broccoli to Grow
For a family of 4, plant approximately 12 broccoli plants in about 30 sq ft. In Miami-Dade County's 365-day season, you'll have plenty of time for a full harvest. Plan your garden layout →
Broccoli Water Budget
Monthly Watering Guide for Broccoli
Broccoli needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Broccoli Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | 4.3" | 2.9" | 1.4" | 💧 Light watering |
| Feb | 4.3" | 2.9" | 1.4" | 💧 Light watering |
| Mar | 4.3" | 3.4" | 0.9" | 💧 Light watering |
| Apr | 4.3" | 2.5" | 1.8" | 💧 Light watering |
| May | 4.3" | 3.8" | 0.5" | 💧 Light watering |
| Jun | 4.3" | 8.1" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 9.5" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 8.6" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 7.1" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 5" | 0" | ✅ Rainfall sufficient |
| Nov | 4.3" | 2.3" | 2" | 💧 Light watering |
| Dec | 4.3" | 2.7" | 1.6" | 💧 Light watering |
Water needs are for active growing months only (Jan–Dec in Miami-Dade County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Broccoli 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.
Broccoli Planting Timeline — Key Biscayne, FL
Broccoli Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | December 4 | Dec 4 – Dec 18 |
| Transplant Outdoors | January 1 | Jan 1 – Jan 15 |
| Direct Sow | December 11 | Dec 11 – Jan 1 |
| Harvest | March 5 | Mar 5 – Apr 16 |
| Fall Sowing | November 5 | Nov 5 – Nov 19 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Transplant Outdoors Direct Sow |
| February | — |
| March | Harvest |
| April | Harvest |
| May | — |
| June | — |
| July | — |
| August | — |
| September | — |
| October | — |
| November | Fall Sowing |
| December | Start Indoors Direct Sow |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · 1-2 times/week
📅 Days to Maturity
60–90 days
🧪 Soil pH
Needs 6–7 · Your soil: too_acidic
🗺️ USDA Zone
Zone 11a
📆 Growing Season
365 days in Miami-Dade County
Growing Tips for Broccoli in Key Biscayne
Sandy soil in Miami-Dade County dries quickly — mulch Broccoli with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
Common pests for Broccoli in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.
General growing tips
Start seeds indoors 6-8 weeks before last frost. Provide consistent moisture to prevent hollow stems. Harvest heads before yellow flowers appear.
Recommended Broccoli Varieties for Key Biscayne
Heat-tolerant broccoli — plant as early spring or fall crop
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Isolate 1/2 mile from other brassicas. Biennial — must overwinter roots.
Broccoli in Other Locations
When should I plant Broccoli in Key Biscayne, FL?
In Key Biscayne, FL, plant Broccoli 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 Key Biscayne, FL for Broccoli?
Key Biscayne sits in USDA Zone 11a. Broccoli grows reliably in zones 2a through 11b, so it's a good fit here.
Can Broccoli grow in Key Biscayne's climate?
Yes — Broccoli grows well in Key Biscayne's temperate climate. Key Biscayne averages a 365-day frost-free season, with last frost around January 1 and first frost around December 31.
Your Miami-Dade County Garden Planner — Free
A 22-page printable planner built for Miami-Dade 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.