When to Plant Snapdragon in Jefferson County, TX
What to do in June
If you only do a handful of things in the garden this June, make it these. They're sequenced around your zone's frost timing.
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Start harvesting snapdragon
Check every 1–2 days. Many of these get tough or go to seed if you wait too long.
Before July arrives, get these ready
- First harvests: snapdragon
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.
Jefferson County, Texas is in USDA Zone 9b. The average last spring frost is February 13 and the first fall frost is December 6, giving you a growing season of approximately 296 days.
At an elevation of 349 feet, Jefferson County receives approximately 64.9 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 101°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.
Jefferson County Soil Profile
Soil Type
Sandy Loam
Soil pH
5.4-6.5
Drainage
Well Drained
Snapdragon 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 Jefferson County
How your county's soil matches Snapdragon's growing requirements.
Soil pH
Your soil pH (5.4–6.5) is more acidic than Snapdragon prefers (6.2–7.0). Add garden lime to raise pH.
Soil Texture
Sandy soil in Jefferson County warms quickly in spring but drains fast. Snapdragon will need more frequent watering and regular compost additions to retain nutrients.
Organic Matter
Organic matter is moderate (2.2%). Annual compost additions will help Snapdragon.
How to Plant Snapdragon
Fall planting: Sow 12 weeks before your first frost date for a fall harvest.
Succession Planting Snapdragon
Sow every 8 weeks. Last sowing by Aug 28 to harvest before frost.
For a dedicated fall crop, sow by Sep 13.
Snapdragon Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
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 | — | 1.6" | 0" | ❄️ Dormant |
| Feb | 4.3" | 2.1" | 2.2" | 🚿 Regular watering |
| Mar | 4.3" | 4.4" | 0" | ✅ Rainfall sufficient |
| Apr | 4.3" | 6.3" | 0" | ✅ Rainfall sufficient |
| May | 4.3" | 9.8" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 10.7" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 8.8" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 6.6" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 6.6" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 4.4" | 0" | ✅ Rainfall sufficient |
| Nov | 4.3" | 2.1" | 2.2" | 🚿 Regular watering |
| Dec | 4.3" | 1.6" | 2.7" | 🚿 Regular watering |
Water needs are for active growing months only (Feb–Dec in Jefferson County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Snapdragon 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.
Snapdragon Planting Timeline — Jefferson County, TX
Snapdragon Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | January 9 | Jan 9 – Jan 23 |
| Direct Sow | December 12 | Dec 12 – Jan 2 |
| Bloom | March 13 | Mar 13 – Jul 24 |
| Fall Sowing | September 13 | Sep 13 – Sep 27 |
· 9" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Transplant Outdoors Direct Sow |
| February | — |
| March | Bloom |
| April | Bloom |
| May | Bloom |
| June | Bloom |
| July | Bloom |
| August | — |
| September | Fall Sowing |
| October | — |
| November | — |
| December | Direct Sow |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · Only during dry spells
📅 Days to Maturity
70–100 days
🧪 Soil pH
Needs 6.2–7 · Your soil: too_acidic
🗺️ USDA Zone
Zone 9b
📆 Growing Season
296 days in Jefferson County
Growing Tips for Snapdragon in Jefferson County
Direct sow Snapdragon outdoors after February 13 in Jefferson County when soil has warmed and frost danger has passed.
Sandy soil in Jefferson County dries quickly — mulch Snapdragon with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
With summer highs reaching 101°F in Jefferson County, provide afternoon shade for Snapdragon and water deeply in the morning.
General growing tips
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 Jefferson County, TX?
Jefferson County is in Zone 9b with an average last frost of February 13. Plan your Snapdragon planting based on this frost date — see the calendar above for exact timing.
What planting zone is Jefferson County, TX?
Jefferson County, Texas is in USDA Hardiness Zone 9b. The average last spring frost is February 13 and first fall frost is December 6.
Your Jefferson County Garden Planner — Free
A 22-page printable planner built for Jefferson County (Zone 9b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.