When to Plant Tomatoes in Jefferson County, TX
Tomatoes are the most popular home garden crop, available in thousands of varieties from tiny cherries to massive beefsteaks. They are warm-season plants needing full sun.
Jefferson County, Texas is in USDA Zone 9a. The average last spring frost is February 13 and the first fall frost is December 6, giving you a growing season of approximately 296 days.
At an elevation of 349 feet, Jefferson County receives approximately 64.9 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 101°F, so Tomatoes may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Tomatoes will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Tomatoes root diseases.
Jefferson County Soil Profile
Soil Type
Sandy Loam
Soil pH
5.4-6.5
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 Jefferson County
How your county's soil matches Tomatoes's growing requirements.
Soil pH
Your soil pH (5.4–6.5) is more acidic than Tomatoes prefers (6.0–7.0). Add garden lime to raise pH.
Soil Texture
Sandy soil in Jefferson County warms quickly in spring but drains fast. Tomatoes 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 Tomatoes.
How to Plant Tomatoes
Succession Planting Tomatoes
Sow every 6.9 weeks. Last sowing by Sep 12 to harvest before frost.
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Tomatoes
Tomatoes needs approximately 1.2 inches of water per week (5.2" per month). Here's how your county's rainfall compares month by month.
| Month | Tomatoes Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.6" | 0" | ❄️ Dormant |
| Feb | 5.2" | 2.1" | 3.1" | 🚿 Regular watering |
| Mar | 5.2" | 4.4" | 0.8" | 💧 Light watering |
| Apr | 5.2" | 6.3" | 0" | ✅ Rainfall sufficient |
| May | 5.2" | 9.8" | 0" | ✅ Rainfall sufficient |
| Jun | 5.2" | 10.7" | 0" | ✅ Rainfall sufficient |
| Jul | 5.2" | 8.8" | 0" | ✅ Rainfall sufficient |
| Aug | 5.2" | 6.6" | 0" | ✅ Rainfall sufficient |
| Sep | 5.2" | 6.6" | 0" | ✅ Rainfall sufficient |
| Oct | 5.2" | 4.4" | 0.8" | 💧 Light watering |
| Nov | 5.2" | 2.1" | 3.1" | 🚿 Regular watering |
| Dec | 5.2" | 1.6" | 3.6" | 🚿 Regular watering |
Water needs are for active growing months only (Feb–Dec in Jefferson County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Tomatoes 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.
Tomatoes Planting Timeline — Jefferson County, TX
Tomatoes Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 2 | Jan 2 – Jan 16 |
| Transplant Outdoors | February 20 | Feb 20 – Mar 6 |
| Direct Sow | February 13 | Feb 13 – Mar 6 |
| Harvest | April 24 | Apr 24 – Jul 3 |
Plant 0.5" deep · 24" apart · Rows 36" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | Transplant Outdoors Direct Sow |
| March | Transplant Outdoors Direct Sow |
| April | Harvest |
| May | Harvest |
| June | Harvest |
| July | Harvest |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1.2"/week · 1-2 times/week
📅 Days to Maturity
60–85 days
🧪 Soil pH
Needs 6–7 · Your soil: too_acidic
🗺️ USDA Zone
Zone 9a
📆 Growing Season
296 days in Jefferson County
Growing Tips for Tomatoes in Jefferson County
Direct sow Tomatoes outdoors after February 13 in Jefferson County when soil has warmed and frost danger has passed.
Sandy soil in Jefferson County dries quickly — mulch Tomatoes with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
With summer highs reaching 101°F in Jefferson County, provide afternoon shade for Tomatoes and water deeply in the morning.
Common pests for Tomatoes in this region include tomato hornworm and aphids. Use row covers early in the season and inspect plants weekly.
General growing tips
Start seeds indoors 6-8 weeks before last frost. Bury transplants deep to encourage rooting along the stem. Provide consistent moisture to prevent blossom end rot and cracking.
Recommended Tomatoes Varieties for Jefferson County
Heat-set varieties that pollinate reliably above 90°F
Your long season supports large indeterminate heirloom types
Disease-resistant varieties for your humid climate
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Isolate 25 ft between varieties for purity. Use open-pollinated varieties for true-to-type seeds.
Tomatoes in Other Locations
Frequently Asked Questions
When should I plant Tomatoes in Jefferson County, TX?
Jefferson County is in Zone 9a with an average last frost of February 13. Plan your Tomatoes planting based on this frost date — see the calendar above for exact timing.
What planting zone is Jefferson County, TX?
Jefferson County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is February 13 and first fall frost is December 6.
Plan Your Garden with Confidence
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