When to Plant Sweet Potatoes in San Jacinto County, TX
This month in San Jacinto County, Texas
A quick May briefing for San Jacinto County, Texas gardeners — what's urgent, what's next, and what can wait.
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Basket week: sweet potatoes
If you can't use it all right away, check the food-preservation section of your planner.
Looking ahead to 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.
San Jacinto County, Texas is in USDA Zone 9a. The average last spring frost is February 18 and the first fall frost is December 1, giving you a growing season of approximately 286 days.
At an elevation of 6 feet, San Jacinto County receives approximately 71.3 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 94°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.
San Jacinto County Soil Profile
Soil Type
Sandy Loam
Soil pH
5.3-6.7
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 San Jacinto County
How your county's soil matches Sweet Potatoes's growing requirements.
Soil pH
Your soil pH (5.3–6.7) overlaps with Sweet Potatoes's range (5.5–6.5), though not a perfect match.
Soil Texture
Sandy soil in San Jacinto County warms quickly in spring but drains fast. Sweet Potatoes will need more frequent watering and regular compost additions to retain nutrients.
Organic Matter
Organic matter is moderate (2.2%). Annual compost additions will help 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 | — | 1.7" | 0" | ❄️ Dormant |
| Feb | 4.3" | 2.5" | 1.8" | 💧 Light watering |
| Mar | 4.3" | 4.2" | 0.1" | 💧 Light watering |
| Apr | 4.3" | 8.5" | 0" | ✅ Rainfall sufficient |
| May | 4.3" | 9.5" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 11.4" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 9.2" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 8" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 6.7" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 5.2" | 0" | ✅ Rainfall sufficient |
| Nov | 4.3" | 2.6" | 1.7" | 💧 Light watering |
| Dec | 4.3" | 1.9" | 2.4" | 🚿 Regular watering |
Water needs are for active growing months only (Feb–Dec in San Jacinto 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 — San Jacinto County, TX
Sweet Potatoes Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 7 | Jan 7 – Jan 21 |
| Transplant Outdoors | February 25 | Feb 25 – Mar 11 |
| Direct Sow | February 18 | Feb 18 – Mar 11 |
| Harvest | May 27 | May 27 – Jul 15 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | Transplant Outdoors Direct Sow |
| March | Transplant Outdoors Direct Sow |
| April | — |
| May | Harvest |
| June | Harvest |
| July | Harvest |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · Natural rainfall sufficient
📅 Days to Maturity
90–120 days
🧪 Soil pH
Needs 5.5–6.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 9a
📆 Growing Season
286 days in San Jacinto County
Growing Tips for Sweet Potatoes in San Jacinto County
Direct sow Sweet Potatoes outdoors after February 18 in San Jacinto County when soil has warmed and frost danger has passed.
Sandy soil in San Jacinto 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 San Jacinto County, TX?
San Jacinto County is in Zone 9a with an average last frost of February 18. Plan your Sweet Potatoes planting based on this frost date — see the calendar above for exact timing.
What planting zone is San Jacinto County, TX?
San Jacinto County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is February 18 and first fall frost is December 1.
Your San Jacinto County Garden Planner — Free
A 24-page printable planner built for San Jacinto County (Zone 9a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.