When to Plant Tomatillo in Seminole County, OK
Your May planting checklist for Seminole County, Oklahoma
A quick May briefing for Seminole County, Oklahoma gardeners — what's urgent, what's next, and what can wait.
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Sow tomatillo in trays indoors
These need a head start before your last frost (March 31). Sow into cells now so you're ready to transplant in a few weeks.
June prep starts now
- First harvests: tomatillo
Tomatillos are a Mexican staple that produces tart, green fruits enclosed in papery husks. They are essential for salsa verde and green sauces.
Seminole County, Oklahoma is in USDA Zone 7b. The average last spring frost is March 31 and the first fall frost is November 6, giving you a growing season of approximately 220 days.
At an elevation of 961 feet, Seminole County receives approximately 20.7 inches of rainfall annually with predominantly loam soil. Summer highs average 94°F, providing good warmth for Tomatillo during the growing season.
Seminole County Soil Profile
Soil Type
Loam
Soil pH
6.7-7.5
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 Seminole County
How your county's soil matches Tomatillo's growing requirements.
Soil pH
Your soil pH (6.7–7.5) is more alkaline than Tomatillo prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Seminole County is excellent for Tomatillo — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.9%). Annual compost additions will help Tomatillo.
How to Plant Tomatillo
Succession Planting Tomatillo
Sow every 6.9 weeks. Last sowing by Aug 13 to harvest before frost.
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Tomatillo
Tomatillo needs approximately 1.1 inches of water per week (4.8" per month). Here's how your county's rainfall compares month by month.
| Month | Tomatillo Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 0.6" | 0" | ❄️ Dormant |
| Feb | — | 0.8" | 0" | ❄️ Dormant |
| Mar | 4.8" | 1.4" | 3.4" | 🚿 Regular watering |
| Apr | 4.8" | 2.1" | 2.7" | 🚿 Regular watering |
| May | 4.8" | 3.2" | 1.6" | 💧 Light watering |
| Jun | 4.8" | 3.3" | 1.5" | 💧 Light watering |
| Jul | 4.8" | 2.4" | 2.4" | 🚿 Regular watering |
| Aug | 4.8" | 2.8" | 2" | 💧 Light watering |
| Sep | 4.8" | 1.7" | 3.1" | 🚿 Regular watering |
| Oct | 4.8" | 1.3" | 3.5" | 🚿 Regular watering |
| Nov | 4.8" | 0.8" | 4" | 🚿 Regular watering |
| Dec | — | 0.5" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Seminole County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Tomatillo 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.
Tomatillo Planting Timeline — Seminole County, OK
Tomatillo Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 10 | Feb 10 – Feb 24 |
| Transplant Outdoors | April 14 | Apr 14 – Apr 28 |
| Direct Sow | April 7 | Apr 7 – Apr 28 |
| Harvest | June 16 | Jun 16 – Aug 25 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | — |
| April | Transplant Outdoors Direct Sow |
| May | — |
| June | Harvest |
| July | Harvest |
| August | Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1.1"/week · 2-3 times/week
📅 Days to Maturity
60–85 days
🧪 Soil pH
Needs 6–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 7b
📆 Growing Season
220 days in Seminole County
Growing Tips for Tomatillo in Seminole County
Direct sow Tomatillo outdoors after March 31 in Seminole County when soil has warmed and frost danger has passed.
Common pests for Tomatillo in this region include tomato hornworm and aphids. Use row covers early in the season and inspect plants weekly.
Seminole County receives only 21" of rain annually. Tomatillo needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Start seeds indoors 6-8 weeks before last frost. Plant at least two plants for cross-pollination. Harvest when fruits fill the husk and it begins to split.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Tomatillo in Other Locations
Frequently Asked Questions
When should I plant Tomatillo in Seminole County, OK?
Seminole County is in Zone 7b with an average last frost of March 31. Plan your Tomatillo planting based on this frost date — see the calendar above for exact timing.
What planting zone is Seminole County, OK?
Seminole County, Oklahoma is in USDA Hardiness Zone 7b. The average last spring frost is March 31 and first fall frost is November 6.
Your Seminole County Garden Planner — Free
A 24-page printable planner built for Seminole County (Zone 7b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.