How to Grow Yardlong Bean
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Yardlong Bean
Vigna unguiculata subsp. sesquipedalis
vegetableYardlong beans, also called asparagus beans or snake beans, are a heat-loving legume that produces exceptionally long, slender green pods reaching 12-36 inches in length. Native to Asia, these vigorous vining plants are prized for their tender, crisp pods with a mild flavor similar to green beans but with a slightly sweeter taste. They thrive in warm conditions and are a staple in Asian cuisines.
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Example Yardlong Bean timeline · Pittsburgh, PA (Zone 6b)
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Plant Yardlong Bean
Around Apr 17Near Pittsburgh's average last spring frost.
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Tend & protect
Late spring–summerWatering, feeding, and pest-watch reminders.
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Harvest Yardlong Bean
Around Jun 21≈ 65 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Yardlong Bean dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 9-11; can be grown as an annual in zones 8 and above with warm soil
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Get my Yardlong Bean timeline →Growth Stages
Seedling
7-10 daysTwo cotyledons emerge, followed by true leaves. Plants establish a small root system.
Ensure soil remains moist but not soggy. Provide bright light and warm temperatures (70-85°F). Thin seedlings to proper spacing once they have 2-3 true leaves.
Vegetative Growth
3-4 weeksVigorous vine growth with compound leaves developing. Plants climb or sprawl depending on support structure.
Provide sturdy trellising, stakes, or fencing for vining support. Apply balanced fertilizer every 3-4 weeks. Maintain consistent moisture. Mulch around base to retain moisture and regulate soil temperature.
Flowering
2-3 weeksSmall white, pink, or purple flowers appear along the vines in clusters. Flowers develop into tiny green pods.
Continue regular watering and fertilization. Shift to lower nitrogen fertilizer to promote flowering over excessive foliage. Do not allow soil to dry out during this critical stage.
Pod Development
4-6 weeksYoung pods rapidly elongate, reaching 12-36 inches depending on variety. Pods remain tender and green at harvest maturity.
Pick pods regularly and frequently to encourage continued production. Fertilize every 2 weeks with balanced or slightly phosphorus-rich fertilizer. Maintain even moisture to prevent pod splitting.
Harvest
6-8 weeksMature pods reach desired length (typically 8-12 inches for best tenderness) and are bright green with firm snap.
Harvest regularly every 2-3 days. Pick in the morning when pods are crisp. Continue harvesting to stimulate new pod production. Plants remain productive for 6-8 weeks.
Common Pests
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Spray with strong water jet, use neem oil, introduce ladybugs, or apply insecticidal soap
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Increase humidity, spray with water, apply neem oil or sulfur dust, introduce predatory mites
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Hand-pick beetles and egg clusters, use row covers on young plants, apply spinosad
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Use yellow sticky traps, spray with neem oil or insecticidal soap, encourage parasitic wasps
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Ensure good air circulation, spray with sulfur dust or baking soda solution, remove affected leaves
Uses
Stir-fries and Asian cooking
CulinaryYardlong beans are a staple in Southeast Asian cuisine, commonly used in stir-fries, curries, and braised dishes. Their mild flavor and crisp texture make them versatile for both cooked and raw applications. [source]
Fresh vegetable dishes
CulinaryThe tender young pods can be blanched, steamed, or sautéed as a side dish, and are comparable to asparagus or green beans in preparation and taste. [source]
Dried bean harvest
CulinaryAllow mature pods to dry on the vine and harvest the dried beans inside for storage and use in soups and stews, similar to black-eyed peas. [source]
Nitrogen fixation and soil improvement
HouseholdLike all legumes, yardlong beans fix atmospheric nitrogen through symbiotic relationships with soil bacteria, enriching soil for subsequent crops. [source]
Pollinator attraction
WildlifeThe flowers attract bees and other beneficial pollinators to the garden, supporting broader ecosystem health and increasing yields of nearby plants. [source]
Harvest Tips
Begin harvesting when pods are 8-10 inches long (3-4 days after flowering) before they become tough and stringy. Pick in the morning for maximum crispness and tenderness. Use pruning shears or gently snap pods from the vine. Harvest every 2-3 days to encourage continuous production. Mature pods can reach 24-36 inches but become fibrous and tough; harvest regularly to promote new pod development.
Fun Facts
- 🌱 Yardlong beans get their name from their extraordinary length—some varieties produce pods exceeding 3 feet (36 inches), making them among the longest bean pods in cultivation.
- 🌱 In traditional Asian agriculture, yardlong beans are often intercropped with corn or fruit trees, creating efficient polyculture systems that maximize space and soil nutrition.
- 🌱 The entire pod is edible, including immature pods and the mature dried beans inside, providing dual-purpose harvests from a single plant.
Gardening Terms
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