When to Plant Snapdragon in Walla Walla County, WA
Walla Walla County, Washington gardeners: here's your June plan
June rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Walla Walla County, Washington.
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Start snapdragon under lights
These need a head start before your last frost (April 20). Sow into cells now so you're ready to transplant in a few weeks.
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Harvest snapdragon as they ripen
The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.
To set up a strong July, finish these tasks
- 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.
Walla Walla County, Washington is in USDA Zone 7a. The average last spring frost is April 20 and the first fall frost is October 15, giving you a growing season of approximately 178 days.
At an elevation of 3,151 feet, Walla Walla County receives approximately 23.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Snapdragon during the growing season.
Walla Walla County Soil Profile
Soil Type
Silt Loam
Soil pH
5.2-6.4
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 Walla Walla County
How your county's soil matches Snapdragon's growing requirements.
Soil pH
Your soil pH (5.2–6.4) is more acidic than Snapdragon prefers (6.2–7.0). Add garden lime to raise pH.
Soil Texture
The silt loam soil in Walla Walla County is excellent for Snapdragon — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.2%) — Snapdragon will thrive.
How to Plant Snapdragon
Fall planting: Sow 8 weeks before your first frost date for a fall harvest.
Succession Planting Snapdragon
Sow every 8 weeks. Last sowing by Jul 07 to harvest before frost.
For a dedicated fall crop, sow by Aug 20.
Snapdragon Water Budget
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 | — | 2.9" | 0" | ❄️ Dormant |
| Feb | — | 2.7" | 0" | ❄️ Dormant |
| Mar | — | 2.3" | 0" | ❄️ Dormant |
| Apr | 4.3" | 1.7" | 2.6" | 🚿 Regular watering |
| May | 4.3" | 1.5" | 2.8" | 🚿 Regular watering |
| Jun | 4.3" | 1" | 3.3" | 🚿 Regular watering |
| Jul | 4.3" | 0.4" | 3.9" | 🚿 Regular watering |
| Aug | 4.3" | 0.5" | 3.8" | 🚿 Regular watering |
| Sep | 4.3" | 0.9" | 3.4" | 🚿 Regular watering |
| Oct | 4.3" | 2.2" | 2.1" | 💧 Light watering |
| Nov | — | 3.7" | 0" | ❄️ Dormant |
| Dec | — | 3.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Walla Walla 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 — Walla Walla County, WA
Snapdragon Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 9 | Feb 9 – Feb 23 |
| Transplant Outdoors | April 20 | Apr 20 – May 4 |
| Direct Sow | March 23 | Mar 23 – Apr 13 |
| Bloom | June 29 | Jun 29 – Sep 21 |
| Fall Sowing | August 20 | Aug 20 – Sep 3 |
· 9" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors |
| June | Bloom |
| July | Bloom |
| August | Fall Sowing Bloom |
| September | Fall Sowing Bloom |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · 1-2 times/week
📅 Days to Maturity
70–100 days
🧪 Soil pH
Needs 6.2–7 · Your soil: too_acidic
🗺️ USDA Zone
Zone 7a
📆 Growing Season
178 days in Walla Walla County
Growing Tips for Snapdragon in Walla Walla County
Direct sow Snapdragon outdoors after April 20 in Walla Walla County when soil has warmed and frost danger has passed.
Walla Walla County receives only 24" of rain annually. Snapdragon needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
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 Walla Walla County, WA?
Walla Walla County is in Zone 7a with an average last frost of April 20. Plan your Snapdragon planting based on this frost date — see the calendar above for exact timing.
What planting zone is Walla Walla County, WA?
Walla Walla County, Washington is in USDA Hardiness Zone 7a. The average last spring frost is April 20 and first fall frost is October 15.
Your Walla Walla County Garden Planner — Free
A 22-page printable planner built for Walla Walla County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.