When to Plant Ranunculus in Walla Walla County, WA
Your July planting checklist for Walla Walla County, Washington
Each item below is timed to Walla Walla County, Washington's frost dates and soil temperatures. Skip nothing, stress about nothing.
Looking ahead to August
- Fall sowing: ranunculus
Persian ranunculus (Ranunculus asiaticus) produces multi-petaled blooms that rival roses in intricacy and lushness, in a warm palette of reds, oranges, yellows, pinks, and whites. A cornerstone of the specialty cut flower industry, ranunculus produces long, strong stems ideal for bouquets and arrangements. As a cool-season corm, it performs best in the mild shoulder seasons — planted in fall in warm-winter zones, or in early spring where summers arrive quickly. The 'Elegance', 'Amandine', and 'Tecolote' strains are favorites for both home gardens and commercial growers.
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 Ranunculus during the growing season.
Walla Walla County Soil Profile
Soil Type
Silt Loam
Soil pH
5.2-6.4
Drainage
Well Drained
Ranunculus 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 Ranunculus's growing requirements.
Soil pH
Your soil pH (5.2–6.4) is more acidic than Ranunculus prefers (6.0–6.5). Add garden lime to raise pH.
Soil Texture
The silt loam soil in Walla Walla County is excellent for Ranunculus — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.2%) — Ranunculus will thrive.
How to Plant Ranunculus
Fall planting: Sow 8 weeks before your first frost date for a fall harvest.
Ranunculus Water Budget
Monthly Watering Guide for Ranunculus
Ranunculus needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Ranunculus 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.
Ranunculus 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.
Ranunculus Planting Timeline — Walla Walla County, WA
Ranunculus Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Bloom | September 17 | Sep 17 – Oct 15 |
| Fall Sowing | August 20 | Aug 20 – Sep 3 |
Plant 2" deep · 6" apart · Rows 8" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | — |
| June | — |
| July | — |
| August | Fall Sowing |
| September | Fall Sowing Bloom |
| October | Bloom |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · 1-2 times/week
📅 Days to Maturity
90–120 days
🧪 Soil pH
Needs 6–6.5 · Your soil: too_acidic
🗺️ USDA Zone
Zone 7a
📆 Growing Season
178 days in Walla Walla County
Growing Tips for Ranunculus in Walla Walla County
Direct sow Ranunculus 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. Ranunculus needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Pre-soak corms (which look like small octopus tentacles) in cool water for 2–4 hours before planting; do not over-soak. Plant with tentacles pointing downward, 1–2 inches deep and 6 inches apart. Ranunculus demand excellent drainage — they rot in soggy soil. In fall-planting zones (7+), plant October–November and allow to root through mild winter; blooms arrive in March–May. In zones 6, start corms indoors in late winter and transplant out after last frost for a late-spring bloom. Keep soil consistently moist but never waterlogged during growth. After foliage yellows (post-bloom), stop watering, let corms dry, lift them, and store in a cool dry place until replanting. In zones 8b–10b, corms can often be left in ground year-round.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Ranunculus in Other Locations
Frequently Asked Questions
When should I plant Ranunculus in Walla Walla County, WA?
Walla Walla County is in Zone 7a with an average last frost of April 20. Plan your Ranunculus 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.