What hardiness zones is Phaseolus coccineus 'Scarlet Runner' suitable for?

Phaseolus coccineus 'Scarlet Runner' is a tender perennial (hardy to zone 7) typically grown as an annual, reaching 8-12 feet (2.4-3.6 m) tall with a spread of 12-18 inches (30-45 cm) and a vigorous, twining, climbing habit that wraps counterclockwise around supports. Native to the mountains of Central America, it produces clusters of vivid scarlet-red, papilionaceous (butterfly-shaped) flowers followed by large, flat, rough-textured green pods 6-10 inches (15-25 cm) long containing large seeds that mature from pink-purple to black with red-purple mottling. Both young pods and mature seeds are edible. Days to maturity 60-70 from direct sow for green pods, 90-100 for dry beans. Growth rate is very fast. Prefers cooler temperatures than common beans (P. vulgaris)—sets pods more reliably at 60-75°F (16-24°C). Flowers attract hummingbirds.

Native Range

Phaseolus coccineus is native to the mountains of Central America—Mexico and Guatemala at elevations of 4,000-9,000 feet (1,200-2,700 m).

Suggested Uses

Grown on trellises, arbors, or tepees for culinary and ornamental use—edible young pods, dry shell beans, edible flowers. Vivid scarlet flowers attract hummingbirds. Dual-purpose ornamental/edible. Cool-temperature preference. 60-70 days for pods. Vigorous 8-12 ft climber. Requires sturdy support. Pod set drops above 85°F. Raw mature beans contain phytohemagglutinin—must be thoroughly cooked.

How to Identify

Distinguished from common beans (P. vulgaris) by the scarlet-red (versus white or pink) flowers, the perennial (versus annual) nature, the much larger seeds, the preference for cooler temperatures, and the counterclockwise (versus clockwise) twining. Distinguished from lima beans (P. lunatus) by the climbing (versus bush) habit and the scarlet (versus white-green) flowers. Scarlet runner—vivid scarlet flowers, hummingbird-attracting, dual-purpose pod/dry bean, cool-preference, counterclockwise twining, Central American montane.

Appearance

Size & Dimensions

Height8' - 12'

Width/Spread1' - 1'6"

Colors

Flower Colors

red

Foliage Colors

green

Fall Foliage Colors

no change

Bloom Information

Bloom Period

~10 weeks

Summer Fall

Clusters of vivid scarlet-red papilionaceous flowers continuously from midsummer through fall. Self-pollinating but cross-pollinated by hummingbirds and bumblebees for higher pod set. Flowers edible with a mild bean flavor.

Detailed Descriptions

Flower Description

Vivid scarlet-red; papilionaceous clusters; midsummer-fall

Foliage Description

Medium green; trifoliate; on vigorous twining stems

Growing Conditions

Sun Requirements

Full Sun Partial Shade

Requires 6-10 hours of direct sunlight daily

• Full Sun: 6+ hours of direct sunlight

• Partial Shade: 3-6 hours of direct sunlight

• Full Shade: Less than 3 hours of direct sunlight

Soil Requirements

pH Range6.0 - 7.5(Neutral)

357912

Soil Types

loam

Drainagewell drained

Water & Climate

Water Needs

Medium

Frost Tolerance

tender

Time to Maturity

60-70 days (green pods); 90-100 days (dry beans)

Care & Maintenance

Care Guide

Direct sow after last frost when soil is warm 60°F (16°C). Provide sturdy support—poles, trellis, or tepee 8-12 feet (2.4-3.6 m). Well-drained, fertile soil (pH 6.0-7.5). Nitrogen-fixing—do not over-fertilize. Consistent moisture during flowering. Prefers cool temperatures 60-75°F (16-24°C)—pod set drops above 85°F (29°C). Harvest green pods at 6-8 inches or allow to dry for shell beans.