When to Plant Scarlet Runner Beans in Lake County, CO
May in Lake County, Colorado — your action list
May is a pivotal month for Lake County, Colorado gardens. Focus on these tasks first and you'll set up the rest of the season for success.
June prep starts now
- Direct-sowing: 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.
Lake County, Colorado is in USDA Zone 5a. The average last spring frost is June 21 and the first fall frost is August 30, giving you a growing season of approximately 70 days.
At an elevation of 7,687 feet, Lake County receives approximately 21.2 inches of rainfall annually with predominantly loam soil. Summer highs average 83°F, so choose short-season varieties of Scarlet Runner Beans to ensure they mature before fall.
Lake County Soil Profile
Soil Type
Loam
Soil pH
6.6-8.2
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 Lake County
How your county's soil matches Scarlet Runner Beans's growing requirements.
Soil pH
Your soil pH (6.6–8.2) is more alkaline than Scarlet Runner Beans prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Lake County is excellent for Scarlet Runner Beans — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.9%). Annual compost additions will help Scarlet Runner Beans.
How to Plant Scarlet Runner Beans
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
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 | — | 1.5" | 0" | ❄️ Dormant |
| Feb | — | 1.1" | 0" | ❄️ Dormant |
| Mar | — | 1.8" | 0" | ❄️ Dormant |
| Apr | — | 2.1" | 0" | ❄️ Dormant |
| May | — | 2.7" | 0" | ❄️ Dormant |
| Jun | 4.3" | 1.4" | 2.9" | 🚿 Regular watering |
| Jul | 4.3" | 2.1" | 2.2" | 🚿 Regular watering |
| Aug | 4.3" | 2.2" | 2.1" | 💧 Light watering |
| Sep | — | 1.6" | 0" | ❄️ Dormant |
| Oct | — | 2.1" | 0" | ❄️ Dormant |
| Nov | — | 1.6" | 0" | ❄️ Dormant |
| Dec | — | 1.2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Jun–Aug in Lake 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 — Lake County, CO
Scarlet Runner Beans Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 26 | Apr 26 – May 10 |
| Transplant Outdoors | July 5 | Jul 5 – Jul 19 |
| Direct Sow | June 28 | Jun 28 – Jul 19 |
| Harvest | September 6 | Sep 6 – Oct 11 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | Start Indoors |
| June | Direct Sow |
| July | Transplant Outdoors Direct Sow |
| August | — |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · Natural rainfall sufficient
📅 Days to Maturity
60–80 days
🧪 Soil pH
Needs 6–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 5a
📆 Growing Season
70 days in Lake County
Growing Tips for Scarlet Runner Beans in Lake County
Direct sow Scarlet Runner Beans outdoors after June 21 in Lake County when soil has warmed and frost danger has passed.
Your 70.0-day growing season in Lake County is tight for Scarlet Runner Beans (60.0-80.0 days to maturity). Start indoors and choose early-maturing varieties.
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.
Lake County receives only 21" of rain annually. Scarlet Runner Beans needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
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
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Scarlet Runner Beans in Other Locations
Frequently Asked Questions
When should I plant Scarlet Runner Beans in Lake County, CO?
Lake County is in Zone 5a with an average last frost of June 21. Plan your Scarlet Runner Beans planting based on this frost date — see the calendar above for exact timing.
What planting zone is Lake County, CO?
Lake County, Colorado is in USDA Hardiness Zone 5a. The average last spring frost is June 21 and first fall frost is August 30.
Your Lake County Garden Planner — Free
A 24-page printable planner built for Lake County (Zone 5a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.