When to Plant Scarlet Runner Beans in USDA Zone 4a
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.
In Zone 4a, the average last spring frost is around May 6 and the first fall frost is around September 28, giving you a growing season of approximately 145 days.
Scarlet Runner Beans Planting Timeline — Zone 4a
Where Is USDA Zone 4a?
The map below highlights the states that contain Zone 4a. Click any state to see the Scarlet Runner Beans planting schedule for that location.
Scarlet Runner Beans Planting Calendar — Zone 4a
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 4 | Mar 4 – Mar 18 |
| Transplant Outdoors | May 27 | May 27 – Jun 10 |
| Direct Sow | May 20 | May 20 – Jun 10 |
| Harvest | July 29 | Jul 29 – Sep 2 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | — |
| May | Transplant Outdoors Direct Sow |
| June | Transplant Outdoors Direct Sow |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Free Zone 4a Planting Calendar PDF
Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 4a with start dates, transplant windows, and harvest times.
Growing Conditions
Sun
Full Sun (6-8+ hours)
💧 Water
Moderate — regular watering
Days to Maturity
60–80 days
Soil pH
6 – 7
Zone Temperature Range
-30°F to -25°F average annual minimum
Growing Season
145 days (Zone 4a average)
Planting Specifications
| Planting Depth | 1 inches |
| Plant Spacing | 15 inches apart |
| Row Spacing | 24 inches between rows |
Succession Planting Scarlet Runner Beans in Zone 4a
Sow every 6.9 weeks for continuous harvest throughout the season.
Growing Tips for Scarlet Runner Beans in Zone 4a
Zone 4a has a short growing season (~145 days). Start Scarlet Runner Beans indoors early and use season-extension techniques like row covers and cold frames.
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
Level Up Your Garden
Saving Scarlet Runner Beans Seeds
Recommended for Your Garden
Full-spectrum LED lights for starting seeds indoors when daylight is limited.
Warm soil for faster germination of heat-loving crops like tomatoes and peppers.
Protect plants from frost, wind, and pests while letting light and water through.
Related Plants
Scarlet Runner Beans in Other Zones
Scarlet Runner Beans by State
- Alabama
- Alaska
- Arizona
- Arkansas
- California
- Colorado
- Connecticut
- Delaware
- Florida
- Georgia
- Hawaii
- Idaho
- Illinois
- Indiana
- Iowa
- Kansas
- Kentucky
- Louisiana
- Maine
- Maryland
- Massachusetts
- Michigan
- Minnesota
- Mississippi
- Missouri
- Montana
- Nebraska
- Nevada
- New Hampshire
- New Jersey
- New Mexico
- New York
- North Carolina
- North Dakota
- Ohio
- Oklahoma
- Oregon
- Pennsylvania
- Rhode Island
- South Carolina
- South Dakota
- Tennessee
- Texas
- Utah
- Vermont
- Virginia
- Washington
- West Virginia
- Wisconsin
- Wyoming
Frequently Asked Questions
When should I plant Scarlet Runner Beans in Zone 4a?
In Zone 4a, plan your Scarlet Runner Beans planting around the average last frost date of May 6. Start seeds indoors around March 4. Direct sow outdoors around May 20. Transplant seedlings around May 27.
Can Scarlet Runner Beans grow in Zone 4a?
Yes, Scarlet Runner Beans can grow well in Zone 4a, hardy in USDA zones 3a through 11b. Zone 4a has a growing season of approximately 145 days, which is sufficient for Scarlet Runner Beans (60-80 days to maturity).
When can I harvest Scarlet Runner Beans in Zone 4a?
In Zone 4a, expect to harvest Scarlet Runner Beans from July 29 – September 2. Scarlet Runner Beans takes 60-80 days from planting to harvest.
What is the last frost date for Zone 4a?
The average last spring frost in Zone 4a is around May 6, and the first fall frost is around September 28. This gives a growing season of approximately 145 days. These are 50% probability dates — actual frost dates vary year to year.
What should I plant next to Scarlet Runner Beans?
Good companion plants for Scarlet Runner Beans include Corn, Squash Summer. These companions can help with pest control, pollination, and nutrient sharing.
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