When to Plant Corn in Martin County, FL
Corn is a warm-season grass grown for its sweet ears, which are best eaten soon after harvest. It is wind-pollinated and must be planted in blocks for good kernel fill.
Martin County, Florida is in USDA Zone 10a. 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 Corn during the growing season. Sandy soil warms quickly in spring — great for early planting — but Corn will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Corn root diseases.
Martin County Soil Profile
Soil Type
Sand
Soil pH
5.1-5.7
Drainage
Well Drained
Plant 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 Corn's growing requirements.
Soil pH
Your soil pH (5.1–5.7) is more acidic than 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. Corn will need more frequent watering and regular compost additions to retain nutrients.
Drainage
Drainage is adequate for Corn.
Organic Matter
Organic matter is low (1.5%). Add 2-3 inches of compost before planting Corn.
How to Plant Corn
Succession Planting Corn
Sow every 6.9 weeks. Last sowing by Sep 04 to harvest before frost.
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Corn
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 | 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.
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.
Corn Planting Timeline — Martin County, FL
Corn Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | February 1 | Feb 1 – Feb 22 |
| Harvest | April 5 | Apr 5 – May 31 |
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
60–100 days
🧪 Soil pH
Needs 6–7 · Your soil: too_acidic
🗺️ USDA Zone
Zone 10a
📆 Growing Season
322 days in Martin County
Growing Tips for Corn in Martin County
Direct sow 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 Corn with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
Common pests for 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 rather than single rows for proper pollination. Direct sow after soil reaches 60F. Side-dress with nitrogen when plants are knee-high.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Corn in Other Locations
Frequently Asked Questions
When should I plant Corn in Martin County, FL?
Martin County is in Zone 10a with an average last frost of January 25. Plan your 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 10a. The average last spring frost is January 25 and first fall frost is December 13.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Martin County gardeners in Zone 10a organize planting dates, track what's growing, and never miss a planting window.
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