Green Beans

A favorite in the summer garden, green beans are also called snap beans and string beans although modern varieties nearly always lack a string-like layer on the underside of pods.

Selections

Choose bush varieties for early maturity with no need for support.
Choose pole bean varieties for harvests over a long period; provide sturdy trellising 6-8 ft. tall.
Consider types of pods when selecting a green bean variety—standard round, flat, green, purple, yellow, waxy—each with a slightly different and distinctive flavor.
Provide support for 3-5 ft. half-runner beans for even heavier crops on upright growth.
Select among many dozens of varieties, all suitable for growing in Sonoma County. ‘Blue Lake’ and ‘Kentucky Wonder’ are among the most popular; ‘Kentucky Blue’ combines their qualities.
Attract hummingbirds with red blossoms of fast-growing scarlet runner beans for both food and ornamental value. Their continued blossoming and fruiting may suffer in very hot microclimates.

Planting and Harvesting

Wait to plant until all danger of frost is past and soil is warm, usually when daytime temperatures are regularly above 70 degrees and soil is above 60 degrees, May-July.
Follow package directions when sowing seeds for planting depth and spacing in soil amended with compost. Seeds and roots may rot in cool, wet clay soil.
Expect sprouting in 7-14 days depending on variety and weather; keep soil moist until germination, then evenly moist but never soggy.
Plant bush types every 2-3 weeks from May to July for a continued harvest throughout summer and early fall.
Consider trellising pole varieties with a tripod support for ease of harvesting. Use three wooden poles lashed together at the top with 5-6 seeds planted at the base of poles.
Pick all types of beans frequently, every few days, before pods begin to bulge to sustain continuous and high quality production.

Care and Problems

Apply 3-4 in. of compost or other organic mulch to soil beds after shoots are 2 in. tall to keep soil cool, retain moisture, and inhibit weeds.
Maintain even moisture in the root zone, particularly during bloom periods and when beans form. Dry soil toughens beans and invites pests, such as aphids, spider mites, and whiteflies.
Side dress with organic fertilizer if production slows.
Watch for yellowing leaves, a sign of overwatering. Whitish stippling of leaf surfaces from spider mites can be controlled by washing leaf surfaces with a soap solution.
Delay planting to reduce presence of greenish yellow, spotted, cucumber beetles. Handpick when insect populations are low; place spun fiber row covers over young plants or use yellow sticky traps in beds to help control aphids and whiteflies.

Additional Information

Sonoma County Master Gardener Vegetable Planting Summary.
https://sonomamg.ucanr.edu/Food_Gardening_with_Less_Water/
http://ipm.ucanr.edu/home-and-landscape/beans/index.html
http://ipm.ucanr.edu/home-and-landscape/beans/cultural-tips/

February 2022