When to Plant Snapdragon in Dallam County, TX
Snapdragons (Antirrhinum majus) are classic cool-season annuals whose upright spikes of dragon-lipped flowers are among spring's most dramatic displays. Tolerating light frosts, they bloom from early spring until summer heat shuts them down — then often revive in fall. In zones 9-11 they are grown as fall-planted winter annuals and may re-seed to naturalize.
Dallam County, Texas is in USDA Zone 6b. The average last spring frost is April 26 and the first fall frost is October 14, giving you a growing season of approximately 171 days.
At an elevation of 3,388 feet, Dallam County receives approximately 54.4 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 96°F, so Snapdragon may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Snapdragon will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Snapdragon root diseases.
Dallam County Soil Profile
Soil Type
Sandy Loam
Soil pH
7.9-8.4
Drainage
Well Drained
Monthly Watering Guide for Snapdragon
Snapdragon needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Snapdragon Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 4" | 0" | ❄️ Dormant |
| Feb | — | 3" | 0" | ❄️ Dormant |
| Mar | — | 2.5" | 0" | ❄️ Dormant |
| Apr | 4.3" | 1.7" | 2.6" | 🚿 Regular watering |
| May | 4.3" | 1" | 3.3" | 🚿 Regular watering |
| Jun | 4.3" | 1.7" | 2.6" | 🚿 Regular watering |
| Jul | 4.3" | 9.9" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 11.7" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 8" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 4" | 0.3" | 💧 Light watering |
| Nov | — | 3.3" | 0" | ❄️ Dormant |
| Dec | — | 3.4" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Dallam County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Snapdragon Planting Timeline — Dallam County, TX
Snapdragon Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 15 | Feb 15 – Mar 1 |
| Transplant Outdoors | April 26 | Apr 26 – May 10 |
| Direct Sow | April 5 | Apr 5 – Apr 26 |
| Bloom | July 5 | Jul 5 – Sep 20 |
· 9" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors |
| June | — |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Moderate — regular watering
📅 Days to Maturity
70–100 days
🧪 Soil pH
Needs 6.2–7 · Your soil: N/A
🗺️ USDA Zone
Zone 6b
📆 Growing Season
171 days in Dallam County
Growing Tips for Dallam County
Start indoors 10-12 weeks before last frost; seeds need light to germinate — press into moist medium and do not cover. Transplant after hardening off, even if light frosts remain. Pinch seedlings once to encourage branching. Deadhead to prolong blooming. In zones 8-11, sow in fall for a winter-to-spring show. Tall varieties (24-36") make excellent cut flowers.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Snapdragon in Other Locations
Frequently Asked Questions
When should I plant Snapdragon in Dallam County, TX?
Dallam County is in Zone 6b with an average last frost of April 26. Plan your Snapdragon planting based on this frost date — see the calendar above for exact timing.
What planting zone is Dallam County, TX?
Dallam County, Texas is in USDA Hardiness Zone 6b. The average last spring frost is April 26 and first fall frost is October 14.
Your Dallam County Garden Planner — Free
A 22-page printable planner built for Dallam County (Zone 6b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.