When to Plant Scarlet Runner Beans in Navajo County, AZ
What to do in May
If you only do a handful of things in the garden this May, make it these. They're sequenced around your zone's frost timing.
-
Harden off and plant scarlet runner beans
Pick a cloudy afternoon or evening to plant. Less transplant shock, and your seedlings will barely blink.
-
Put scarlet runner beans seeds straight in the ground
Rake a smooth bed, make a shallow furrow, drop seeds at the spacing on the packet, water gently, walk away.
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.
Navajo County, Arizona is in USDA Zone 7a. The average last spring frost is May 2 and the first fall frost is October 16, giving you a growing season of approximately 167 days.
At an elevation of 5,528 feet, Navajo County receives approximately 15.8 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 94°F, providing good warmth for Scarlet Runner Beans during the growing season. Sandy soil warms quickly in spring — great for early planting — but Scarlet Runner Beans will need more frequent watering and organic matter to retain nutrients. With low rainfall, drip irrigation is essential for growing Scarlet Runner Beans successfully. Mulch heavily to conserve soil moisture.
Navajo County Soil Profile
Soil Type
Sandy Loam
Soil pH
7.3-8.3
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 Navajo County
How your county's soil matches Scarlet Runner Beans's growing requirements.
Soil pH
Your soil pH (7.3–8.3) is more alkaline than Scarlet Runner Beans prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
Sandy soil in Navajo County warms quickly in spring but drains fast. Scarlet Runner Beans will need more frequent watering and regular compost additions to retain nutrients.
Drainage
Drainage is adequate for Scarlet Runner Beans.
Organic Matter
Organic matter is low (0.7%). Add 2-3 inches of compost before planting Scarlet Runner Beans.
How to Plant Scarlet Runner Beans
Succession Planting Scarlet Runner Beans
Sow every 6.9 weeks. Last sowing by Jul 28 to harvest before frost.
Plant Water Budget
Water stress score is 10/10 — 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 | — | 1.3" | 0" | ❄️ Dormant |
| Feb | — | 1" | 0" | ❄️ Dormant |
| Mar | — | 0.9" | 0" | ❄️ Dormant |
| Apr | — | 0.6" | 0" | ❄️ Dormant |
| May | 4.3" | 0.3" | 4" | 🚿 Regular watering |
| Jun | 4.3" | 0.6" | 3.7" | 🚿 Regular watering |
| Jul | 4.3" | 2.4" | 1.9" | 💧 Light watering |
| Aug | 4.3" | 3.5" | 0.8" | 💧 Light watering |
| Sep | 4.3" | 2" | 2.3" | 🚿 Regular watering |
| Oct | 4.3" | 1.3" | 3" | 🚿 Regular watering |
| Nov | — | 0.8" | 0" | ❄️ Dormant |
| Dec | — | 1.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in Navajo 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 — Navajo County, AZ
Scarlet Runner Beans Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 14 | Mar 14 – Mar 28 |
| Transplant Outdoors | May 16 | May 16 – May 30 |
| Direct Sow | May 9 | May 9 – May 30 |
| Harvest | July 18 | Jul 18 – Aug 22 |
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 | — |
| July | Harvest |
| August | Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · 2-3 times/week
📅 Days to Maturity
60–80 days
🧪 Soil pH
Needs 6–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 7a
📆 Growing Season
167 days in Navajo County
Growing Tips for Scarlet Runner Beans in Navajo County
Direct sow Scarlet Runner Beans outdoors after May 02 in Navajo County when soil has warmed and frost danger has passed.
Sandy soil in Navajo County dries quickly — mulch Scarlet Runner Beans with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
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.
Navajo County receives only 16" 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
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 Navajo County, AZ?
Navajo County is in Zone 7a with an average last frost of May 2. Plan your Scarlet Runner Beans planting based on this frost date — see the calendar above for exact timing.
What planting zone is Navajo County, AZ?
Navajo County, Arizona is in USDA Hardiness Zone 7a. The average last spring frost is May 2 and first fall frost is October 16.
Your Navajo County Garden Planner — Free
A 24-page printable planner built for Navajo 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.