When to Plant Cosmos in Pecos County, TX
Cosmos (Cosmos bipinnatus) is an airy, feathery-foliaged cottage garden annual from Mexico that thrives on neglect. It produces delicate daisy-like blooms in shades of pink, white, and magenta from midsummer until frost. Cosmos is a prolific self-sower — once established in a garden it often returns year after year without replanting. Excellent habitat plant for beneficial insects.
Pecos County, Texas is in USDA Zone 8b. The average last spring frost is March 13 and the first fall frost is November 15, giving you a growing season of approximately 247 days.
At an elevation of 1,445 feet, Pecos County receives approximately 42.2 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 103°F, so Cosmos may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Cosmos will need more frequent watering and organic matter to retain nutrients.
Pecos County Soil Profile
Soil Type
Sandy Loam
Soil pH
7.4-8.6
Drainage
Well Drained
Monthly Watering Guide for Cosmos
Cosmos needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Cosmos Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 2.6" | 0" | ❄️ Dormant |
| Feb | — | 2.3" | 0" | ❄️ Dormant |
| Mar | 4.3" | 2.6" | 1.7" | 💧 Light watering |
| Apr | 4.3" | 1.6" | 2.7" | 🚿 Regular watering |
| May | 4.3" | 0.9" | 3.4" | 🚿 Regular watering |
| Jun | 4.3" | 1.6" | 2.7" | 🚿 Regular watering |
| Jul | 4.3" | 7.8" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 8.8" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 5.6" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 3.6" | 0.7" | 💧 Light watering |
| Nov | 4.3" | 2.3" | 2" | 💧 Light watering |
| Dec | — | 2.6" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Pecos County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Cosmos Planting Timeline — Pecos County, TX
Cosmos Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 13 | Feb 13 – Feb 27 |
| Transplant Outdoors | February 20 | Feb 20 – Mar 6 |
| Direct Sow | February 20 | Feb 20 – Mar 13 |
| Bloom | May 1 | May 1 – Oct 2 |
Plant 0.3" deep · 12" apart · Rows 18" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors Transplant Outdoors Direct Sow |
| March | Transplant Outdoors Direct Sow |
| April | — |
| May | Bloom |
| June | Bloom |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Low — drought tolerant
📅 Days to Maturity
60–90 days
🧪 Soil pH
Needs 6–8 · Your soil: N/A
🗺️ USDA Zone
Zone 8b
📆 Growing Season
247 days in Pecos County
Growing Tips for Pecos County
Direct-sow after last frost; cosmos germinates readily at 65-80°F in 7-10 days. Avoid rich soil — excess fertility produces lush foliage at the expense of blooms. Cosmos tolerates poor, dry soil exceptionally well. Pinch seedlings at 8 inches to encourage branching. Self-sows freely; allow some seed heads to mature and drop for a no-fuss perennial effect in warm climates.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Cosmos in Other Locations
Frequently Asked Questions
When should I plant Cosmos in Pecos County, TX?
Pecos County is in Zone 8b with an average last frost of March 13. Plan your Cosmos planting based on this frost date — see the calendar above for exact timing.
What planting zone is Pecos County, TX?
Pecos County, Texas is in USDA Hardiness Zone 8b. The average last spring frost is March 13 and first fall frost is November 15.
Your Pecos County Garden Planner — Free
A 22-page printable planner built for Pecos County (Zone 8b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.