When to Plant Cilantro in Seminole County, OK
May in Seminole County, Oklahoma — your action list
We've pulled the most time-sensitive tasks for Seminole County, Oklahoma this May and put them front and centre. Tackle them in order.
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Indoor seed-starting week for cilantro
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.
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Start harvesting cilantro
The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.
Get ahead of June
- First harvests: cilantro
Cilantro is a dual-purpose herb providing fresh leaves (cilantro) and dried seeds (coriander). It bolts quickly in heat, producing flowers beloved by beneficial insects.
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 Cilantro 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 Cilantro's growing requirements.
Soil pH
Your soil pH (6.7–7.5) is more alkaline than Cilantro prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Seminole County is excellent for Cilantro — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.9%). Annual compost additions will help Cilantro.
How to Plant Cilantro
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Cilantro
Sow every 4.6 weeks. Last sowing by Sep 07 to harvest before frost.
For a dedicated fall crop, sow by Aug 28.
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Cilantro
Cilantro needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.
| Month | Cilantro Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 0.6" | 0" | ❄️ Dormant |
| Feb | — | 0.8" | 0" | ❄️ Dormant |
| Mar | 2.2" | 1.4" | 0.8" | 💧 Light watering |
| Apr | 2.2" | 2.1" | 0.1" | 💧 Light watering |
| May | 2.2" | 3.2" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 3.3" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 2.4" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 2.8" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 1.7" | 0.5" | 💧 Light watering |
| Oct | 2.2" | 1.3" | 0.9" | 💧 Light watering |
| Nov | 2.2" | 0.8" | 1.4" | 🚿 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.
Cilantro 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.
Cilantro Planting Timeline — Seminole County, OK
Cilantro Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 24 | Feb 24 – Mar 10 |
| Transplant Outdoors | March 24 | Mar 24 – Apr 7 |
| Direct Sow | March 17 | Mar 17 – Apr 7 |
| Harvest | May 5 | May 5 – Jul 7 |
| Fall Sowing | August 28 | Aug 28 – Sep 11 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors Transplant Outdoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | Harvest |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
0.5"/week · Only during dry spells
📅 Days to Maturity
40–60 days
🧪 Soil pH
Needs 6–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 7b
📆 Growing Season
220 days in Seminole County
Growing Tips for Cilantro in Seminole County
Direct sow Cilantro outdoors after March 31 in Seminole County when soil has warmed and frost danger has passed.
Summer highs in Seminole County reach 94°F — grow Cilantro as a spring or fall crop. Use shade cloth if planting in summer.
Your generous 220.0-day season in Seminole County allows multiple plantings of Cilantro. Sow every 20.0 days for continuous harvest.
Common pests for Cilantro in this region include carrot rust fly and parsleyworm. Use row covers early in the season and inspect plants weekly.
General growing tips
Succession sow every 2-3 weeks. Provide afternoon shade in warm weather. Harvest leaves before flowering or allow some plants to go to seed for coriander and self-sowing.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Cilantro in Other Locations
Frequently Asked Questions
When should I plant Cilantro in Seminole County, OK?
Seminole County is in Zone 7b with an average last frost of March 31. Plan your Cilantro 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.