When to plant Sweet Corn in Martin County, FL
Sweet Corn planted in Martin County between February 1 and February 22 matures in 60–90 days — well before the December 13 first frost.
When to Plant Sweet Corn in Martin County, FL
This month in Martin County, Florida
Your Martin County, Florida garden is entering a new phase. Here's what's on the schedule for August and why each task matters now.
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Plant fall tomatoes & peppers
Late August is your fall transplant window. Pick heat-tolerant determinate tomatoes (Heatmaster, Solar Fire, Phoenix). They'll set fruit through fall.
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Direct-sow brassicas indoors or in shade
Broccoli, cauliflower, cabbage, Brussels sprouts germinate better in cooler conditions. Start indoors or under shade cloth, transplant in September.
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Refresh mulch & drip lines
Check drip irrigation for clogs (afternoon thunderstorm grit). Top off mulch in all beds before the cool-season crops go in.
Sweet corn is bred for high sugar content in its kernels, which convert to starch rapidly after harvest. Modern supersweet varieties hold their sweetness longer.
Martin County, Florida is in USDA Zone 10b. The average last spring frost is January 25 and the first fall frost is December 13, giving you a growing season of approximately 322 days.
At an elevation of 80 feet, Martin County receives approximately 56.3 inches of rainfall annually with predominantly sand soil. Summer highs average 88°F, providing good warmth for Sweet Corn during the growing season. Sandy soil warms quickly in spring — great for early planting — but Sweet Corn will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Sweet Corn root diseases.
Martin County Soil Profile
Soil Type
Sand
Soil pH
5.1-5.7
Drainage
Well Drained
Sweet Corn 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 Martin County
How your county's soil matches Sweet Corn's growing requirements.
Soil pH
Your soil pH (5.1–5.7) is more acidic than Sweet Corn prefers (6.0–7.0). Add garden lime to raise pH.
Soil Texture
Sandy soil in Martin County warms quickly in spring but drains fast. Sweet Corn will need more frequent watering and regular compost additions to retain nutrients.
Drainage
Drainage is adequate for Sweet Corn.
Organic Matter
Organic matter is low (1.5%). Add 2-3 inches of compost before planting Sweet Corn.
How to Plant Sweet Corn
Succession Planting Sweet Corn
Sow every 6.9 weeks. Last sowing by Sep 14 to harvest before frost.
Sweet Corn Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Sweet Corn
Sweet Corn needs approximately 1.5 inches of water per week (6.5" per month). Here's how your county's rainfall compares month by month.
| Month | Sweet Corn Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | 6.5" | 2.8" | 3.7" | 🚿 Regular watering |
| Feb | 6.5" | 3.1" | 3.4" | 🚿 Regular watering |
| Mar | 6.5" | 3" | 3.5" | 🚿 Regular watering |
| Apr | 6.5" | 2.3" | 4.2" | 🚿 Regular watering |
| May | 6.5" | 3.4" | 3.1" | 💧 Light watering |
| Jun | 6.5" | 8.6" | 0" | ✅ Rainfall sufficient |
| Jul | 6.5" | 7.9" | 0" | ✅ Rainfall sufficient |
| Aug | 6.5" | 8.4" | 0" | ✅ Rainfall sufficient |
| Sep | 6.5" | 8.2" | 0" | ✅ Rainfall sufficient |
| Oct | 6.5" | 4.2" | 2.3" | 💧 Light watering |
| Nov | 6.5" | 2.2" | 4.3" | 🚿 Regular watering |
| Dec | 6.5" | 2.1" | 4.4" | 🚿 Regular watering |
Water needs are for active growing months only (Jan–Dec in Martin County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Sweet Corn 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.
Sweet Corn Planting Timeline — Martin County, FL
Sweet Corn Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | February 1 | Feb 1 – Feb 22 |
| Harvest | April 5 | Apr 5 – May 17 |
Plant 1" deep · 12" apart · Rows 36" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Direct Sow |
| March | — |
| April | Harvest |
| May | Harvest |
| June | — |
| July | — |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1.5"/week · 2-3 times/week
📅 Days to Maturity
60–90 days
🧪 Soil pH
Needs 6–7 · Your soil: too_acidic
🗺️ USDA Zone
Zone 10b
📆 Growing Season
322 days in Martin County
Growing Tips for Sweet Corn in Martin County
Direct sow Sweet Corn outdoors after January 25 in Martin County when soil has warmed and frost danger has passed.
Sandy soil in Martin County dries quickly — mulch Sweet Corn with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
Common pests for Sweet Corn in this region include corn earworm and corn borers. Use row covers early in the season and inspect plants weekly.
General growing tips
Plant in blocks of at least 4 rows for wind pollination. Direct sow after soil is warm. Isolate supersweet varieties from other corn types to prevent cross-pollination.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Sweet Corn in Other Locations
Frequently Asked Questions
When should I plant Sweet Corn in Martin County, FL?
Martin County is in Zone 10b with an average last frost of January 25. Plan your Sweet Corn planting based on this frost date — see the calendar above for exact timing.
What planting zone is Martin County, FL?
Martin County, Florida is in USDA Hardiness Zone 10b. The average last spring frost is January 25 and first fall frost is December 13.
When should I plant Sweet Corn in Martin County, FL?
In Martin County, FL, plant Sweet Corn after the last frost (around January 25) and before the first frost (around December 13). Best results when soil holds above 50°F.
What growing zone is Martin County, FL for Sweet Corn?
Martin County sits in USDA Zone 10b. Sweet Corn grows reliably in zones 3a through 11b, so it's a good fit here.
Can Sweet Corn grow in Martin County's climate?
Yes — Sweet Corn grows well in Martin County's temperate climate. Martin County averages a 323-day frost-free season, with last frost around January 25 and first frost around December 13.
Your Martin County Garden Planner — Free
A 22-page printable planner built for Martin County (Zone 10b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.