When to Plant Scarlet Runner Beans in Mason County, WA
Top priorities for Mason County, Washington gardeners in May
A quick May briefing for Mason County, Washington gardeners — what's urgent, what's next, and what can wait.
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Move scarlet runner beans from tray to bed
Your last frost (April 18) has passed. These warm-season crops can handle outdoor soil now.
Before June arrives, get these ready
- Starting indoors: scarlet runner beans
Scarlet runner beans are ornamental and edible climbing beans with vivid red flowers that attract hummingbirds. Both the young pods and mature beans are edible.
Mason County, Washington is in USDA Zone 8b. The average last spring frost is April 18 and the first fall frost is October 29, giving you a growing season of approximately 194 days.
At an elevation of 230 feet, Mason County receives approximately 36.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Scarlet Runner Beans during the growing season.
Mason County Soil Profile
Soil Type
Silt Loam
Soil pH
5.4-6.7
Drainage
Well Drained
Plant 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 Mason County
How your county's soil matches Scarlet Runner Beans's growing requirements.
Soil pH
Your soil pH (5.4–6.7) overlaps with Scarlet Runner Beans's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Mason County is excellent for Scarlet Runner Beans — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (5.3%) — Scarlet Runner Beans will thrive.
How to Plant Scarlet Runner Beans
Succession Planting Scarlet Runner Beans
Sow every 6.9 weeks. Last sowing by Aug 10 to harvest before frost.
Plant Water Budget
Monthly Watering Guide for Scarlet Runner Beans
Scarlet Runner Beans needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Scarlet Runner Beans Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 5" | 0" | ❄️ Dormant |
| Feb | — | 3.7" | 0" | ❄️ Dormant |
| Mar | — | 4.1" | 0" | ❄️ Dormant |
| Apr | 4.3" | 2.9" | 1.4" | 💧 Light watering |
| May | 4.3" | 1.8" | 2.5" | 🚿 Regular watering |
| Jun | 4.3" | 1.5" | 2.8" | 🚿 Regular watering |
| Jul | 4.3" | 0.6" | 3.7" | 🚿 Regular watering |
| Aug | 4.3" | 0.7" | 3.6" | 🚿 Regular watering |
| Sep | 4.3" | 1.3" | 3" | 🚿 Regular watering |
| Oct | 4.3" | 3.2" | 1.1" | 💧 Light watering |
| Nov | — | 6.5" | 0" | ❄️ Dormant |
| Dec | — | 5.3" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Mason County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Scarlet Runner Beans 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.
Scarlet Runner Beans Planting Timeline — Mason County, WA
Scarlet Runner Beans Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 28 | Feb 28 – Mar 14 |
| Transplant Outdoors | May 2 | May 2 – May 16 |
| Direct Sow | April 25 | Apr 25 – May 16 |
| Harvest | July 4 | Jul 4 – Aug 8 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors |
| April | Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Harvest |
| August | Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · Only during dry spells
📅 Days to Maturity
60–80 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 8b
📆 Growing Season
194 days in Mason County
Growing Tips for Scarlet Runner Beans in Mason County
Direct sow Scarlet Runner Beans outdoors after April 18 in Mason County when soil has warmed and frost danger has passed.
Common pests for Scarlet Runner Beans in this region include bean beetles and aphids. Use row covers early in the season and inspect plants weekly.
General growing tips
Provide tall trellising for vigorous vines. Direct sow after frost. Harvest pods young for snap beans or let mature for shelling beans. Tubers are perennial in mild climates.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Scarlet Runner Beans in Other Locations
Frequently Asked Questions
When should I plant Scarlet Runner Beans in Mason County, WA?
Mason County is in Zone 8b with an average last frost of April 18. Plan your Scarlet Runner Beans planting based on this frost date — see the calendar above for exact timing.
What planting zone is Mason County, WA?
Mason County, Washington is in USDA Hardiness Zone 8b. The average last spring frost is April 18 and first fall frost is October 29.
Your Mason County Garden Planner — Free
A 24-page printable planner built for Mason 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.