When to Plant Sweet Potatoes in Martin County, FL
May to-do list for Martin County, Florida
Each item below is timed to Martin County, Florida's frost dates and soil temperatures. Skip nothing, stress about nothing.
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Collect sweet potatoes at their peak
The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.
A few tasks this May that'll pay off in June
- First harvests: sweet potatoes
Sweet potatoes are a warm-season root crop that produces nutritious, sweet tubers in orange, white, and purple varieties. They need a long, hot growing season.
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 Potatoes during the growing season. Sandy soil warms quickly in spring — great for early planting — but Sweet Potatoes will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Sweet Potatoes 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 Sweet Potatoes's growing requirements.
Soil pH
Your soil pH (5.1–5.7) is more acidic than Sweet Potatoes prefers (5.5–6.5). Add garden lime to raise pH.
Soil Texture
Sandy soil in Martin County warms quickly in spring but drains fast. Sweet Potatoes will need more frequent watering and regular compost additions to retain nutrients.
Drainage
Drainage is adequate for Sweet Potatoes.
Organic Matter
Organic matter is low (1.5%). Add 2-3 inches of compost before planting Sweet Potatoes.
How to Plant Sweet Potatoes
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Sweet Potatoes
Sweet Potatoes needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Sweet Potatoes Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | 4.3" | 2.8" | 1.5" | 💧 Light watering |
| Feb | 4.3" | 3.1" | 1.2" | 💧 Light watering |
| Mar | 4.3" | 3" | 1.3" | 💧 Light watering |
| Apr | 4.3" | 2.3" | 2" | 💧 Light watering |
| May | 4.3" | 3.4" | 0.9" | 💧 Light watering |
| Jun | 4.3" | 8.6" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 7.9" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 8.4" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 8.2" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 4.2" | 0.1" | 💧 Light watering |
| Nov | 4.3" | 2.2" | 2.1" | 💧 Light watering |
| Dec | 4.3" | 2.1" | 2.2" | 🚿 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 Potatoes 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 Potatoes Planting Timeline — Martin County, FL
Sweet Potatoes Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | December 14 | Dec 14 – Dec 28 |
| Transplant Outdoors | February 1 | Feb 1 – Feb 15 |
| Direct Sow | January 25 | Jan 25 – Feb 15 |
| Harvest | May 3 | May 3 – Jun 21 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Direct Sow |
| February | Transplant Outdoors Direct Sow |
| March | — |
| April | — |
| May | Harvest |
| June | Harvest |
| July | — |
| August | — |
| September | — |
| October | — |
| November | — |
| December | Start Indoors |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · 1-2 times/week
📅 Days to Maturity
90–120 days
🧪 Soil pH
Needs 5.5–6.5 · Your soil: too_acidic
🗺️ USDA Zone
Zone 10b
📆 Growing Season
322 days in Martin County
Growing Tips for Sweet Potatoes in Martin County
Direct sow Sweet Potatoes 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 Potatoes with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
General growing tips
Plant slips (rooted sprouts) after soil is thoroughly warm. Build raised mounds for better root development. Cure harvested roots at 80-85F for 10 days to develop sweetness.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Sweet Potatoes in Other Locations
Frequently Asked Questions
When should I plant Sweet Potatoes in Martin County, FL?
Martin County is in Zone 10b with an average last frost of January 25. Plan your Sweet Potatoes 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.
Your Martin County Garden Planner — Free
A 24-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.