When to Plant Cilantro in Sweetwater County, WY
May in Sweetwater County, Wyoming — your action list
We've pulled the most time-sensitive tasks for Sweetwater County, Wyoming this May and put them front and centre. Tackle them in order.
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Time to transplant cilantro
Pinch off the lowest leaves on each seedling before you plant — it reduces water loss while the roots catch up.
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Seed cilantro outdoors
Your soil is 31°F — warm enough for these to germinate without babying.
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.
Sweetwater County, Wyoming is in USDA Zone 5a. The average last spring frost is May 29 and the first fall frost is September 20, giving you a growing season of approximately 114 days.
At an elevation of 7,922 feet, Sweetwater County receives approximately 12.9 inches of rainfall annually with predominantly loam soil. Summer highs average 84°F, so choose short-season varieties of Cilantro to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Cilantro successfully. Mulch heavily to conserve soil moisture.
Sweetwater County Soil Profile
Soil Type
Loam
Soil pH
6.2-7.7
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 Sweetwater County
How your county's soil matches Cilantro's growing requirements.
Soil pH
Your soil pH (6.2–7.7) overlaps with Cilantro's range (6.0–7.0), though not a perfect match.
Soil Texture
The loam soil in Sweetwater County is excellent for Cilantro — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Cilantro.
Organic Matter
Organic matter is moderate (2.4%). 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 Jul 22 to harvest before frost.
For a dedicated fall crop, sow by Jul 12.
Plant Water Budget
Water stress score is 8/10 — 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 | — | 0.8" | 0" | ❄️ Dormant |
| Feb | — | 0.9" | 0" | ❄️ Dormant |
| Mar | — | 1" | 0" | ❄️ Dormant |
| Apr | — | 1.3" | 0" | ❄️ Dormant |
| May | 2.2" | 1.5" | 0.7" | 💧 Light watering |
| Jun | 2.2" | 1" | 1.2" | 🚿 Regular watering |
| Jul | 2.2" | 1.1" | 1.1" | 🚿 Regular watering |
| Aug | 2.2" | 1.3" | 0.9" | 💧 Light watering |
| Sep | 2.2" | 1" | 1.2" | 🚿 Regular watering |
| Oct | — | 1.2" | 0" | ❄️ Dormant |
| Nov | — | 1" | 0" | ❄️ Dormant |
| Dec | — | 0.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Sweetwater 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 — Sweetwater County, WY
Cilantro Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 24 | Apr 24 – May 8 |
| Transplant Outdoors | May 22 | May 22 – Jun 5 |
| Direct Sow | May 15 | May 15 – Jun 5 |
| Harvest | July 3 | Jul 3 – Sep 4 |
| Fall Sowing | July 12 | Jul 12 – Jul 26 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | Start Indoors Transplant Outdoors Direct Sow |
| June | Transplant Outdoors Direct Sow |
| July | Fall Sowing Harvest |
| August | Harvest |
| September | Harvest |
| 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: acceptable
🗺️ USDA Zone
Zone 5a
📆 Growing Season
114 days in Sweetwater County
Growing Tips for Cilantro in Sweetwater County
Direct sow Cilantro outdoors after May 29 in Sweetwater County when soil has warmed and frost danger has passed.
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 Sweetwater County, WY?
Sweetwater County is in Zone 5a with an average last frost of May 29. Plan your Cilantro planting based on this frost date — see the calendar above for exact timing.
What planting zone is Sweetwater County, WY?
Sweetwater County, Wyoming is in USDA Hardiness Zone 5a. The average last spring frost is May 29 and first fall frost is September 20.
Your Sweetwater County Garden Planner — Free
A 24-page printable planner built for Sweetwater County (Zone 5a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.