How to Grow Yard Long Bean

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Yard Long Bean

Vigna unguiculata subsp. sesquipedalis

vegetable

Yard long beans, also called asparagus beans or Thai long beans, are a heat-loving Asian legume producing slender pods that can reach 12-18 inches in length. They grow on vigorous climbing vines and are prized for their tender, slightly sweet flavor and crisp texture. These beans thrive in warm climates and are easier to grow than traditional snap beans in hot weather.

Looking for a specific variety?

Asparagus Bean Thai Long Bean Red-Seeded Long Bean Mosaic Purple-Podded Yard Long Bean Black-Seeded Yard Long Bean

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Example Yard Long Bean timeline · Pittsburgh, PA (Zone 6b)

Plant Yard Long Bean
Around Apr 17

Near Pittsburgh's average last spring frost.
Tend & protect
Late spring–summer

Watering, feeding, and pest-watch reminders.
Harvest Yard Long Bean
Around Jun 16

≈ 60 days after planting

Sample dates for Pittsburgh, PA. Sign up to get exact Yard Long Bean dates for your own zip code.

Growing Conditions

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Sun: Full sun, 6-8 hours daily minimum; benefits from afternoon shade in very hot climates

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Water: Keep soil consistently moist but not waterlogged. Water deeply 1-2 inches per week depending on rainfall and heat. Reduce watering after flowering to concentrate sugars in pods.

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Spacing: 6 inches

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Days to maturity: 60-70 days from sowing to first harvest

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Planting depth: 1 inch

Soil

Type: Well-draining loamy soil rich in organic matter

pH: 6.0-6.8

Amendments:

Compost Aged manure Perlite or sand for drainage Avoid excessive nitrogen fertilizer

Growing Zones

Find your zone →

Best in zones 9b-11; can be grown as an annual summer crop in zones 3-9 with proper timing

9b 10a 10b 11a 11b

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Growth Stages

Seedling

1-2 weeks

Tiny sprouts emerge with cotyledons, followed by first true leaves. Plants are delicate and vulnerable.

Maintain warm soil temperatures (70-85°F minimum). Keep soil consistently moist. Provide protection from direct wind. Thin to proper spacing once plants have 2-3 true leaves.

Vegetative Growth

3-4 weeks

Rapid vine elongation with compound leaflets developing. Tendrils appear for climbing. Plants become bushy and vigorous.

Ensure sturdy trellising or pole support is in place early. Water consistently during dry spells. Apply balanced or slightly low-nitrogen fertilizer every 3-4 weeks. Monitor for pests beginning to colonize foliage.

Flowering

2-3 weeks

Small purple, lavender, or white flowers appear in clusters along the vines. Flowers are fragrant and attractive.

Continue consistent watering but reduce frequency slightly to encourage flowering. Reduce nitrogen to prevent excessive leafy growth. Ensure good air circulation. Do not disturb vines during pollination.

Pod Development & Fruiting

3-4 weeks per flush

Long, slender pods begin forming after flower pollination. Pods grow rapidly and can reach 12-18 inches within 7-10 days.

Maintain steady moisture levels; inconsistent watering causes pod quality issues. Begin harvesting when pods are young and tender (8-10 inches). Regular harvesting encourages continued production. Support heavy pod loads on vines.

Harvest & Senescence

4-6 weeks of peak production

Mature pods ready for harvest. As season progresses, pods may become tough and seedy if left too long. Plants eventually decline as temperatures cool.

Harvest pods every 2-3 days at tender stage (before they reach full length). Keep harvesting to extend production. As fall approaches and temperatures drop below 60°F, plants decline rapidly. Plan succession plantings for continuous harvest.

Companion Planting

Plan your garden →

Plant with:

Marigold Nasturtium Cucumber Squash Corn Basil Dill Garlic

Avoid planting near:

Onions Fennel Kohlrabi Other bean varieties (to prevent cross-pollination and disease spread)

Common Pests

Spray with water to dislodge; use neem oil or insecticidal soap. Increase humidity and air circulation. Heavy infestations may require miticide application.
Spray with strong water stream; apply insecticidal soap or neem oil. Encourage natural predators like ladybugs. Yellow sticky traps can help monitor populations.
Hand-pick beetles and egg clusters. Apply neem oil or spinosad for severe infestations. Plant early in season to avoid peak beetle activity.
Yellow sticky traps for monitoring and control. Spray with insecticidal soap, neem oil, or pyrethrin. Ensure good air circulation to reduce populations.
Regular harvesting removes infested pods. Bt (Bacillus thuringiensis) spray targets larvae. Remove and destroy heavily infested pods.

Uses

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Stir-fries & Asian cuisines

Culinary

Yard long beans are a staple in Southeast Asian cooking, particularly in Thai, Vietnamese, and Chinese cuisines. Their tender texture and slightly sweet flavor make them ideal for quick stir-fries with garlic, chili, and soy sauce. [source]

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Fresh cooking & vegetables

Culinary

The tender young pods can be steamed, boiled, blanched, or sautéed as a side dish. They cook quickly and retain a pleasant crispness when not overcooked. [source]

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Salads & raw preparations

Culinary

Very young, tender pods can be sliced raw into salads or served with dips as a vegetable. Their crisp texture and mild flavor work well in fresh applications. [source]

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Nutritional health benefits

Medicinal

Yard long beans are high in protein, fiber, vitamins (especially folate and vitamin C), and minerals like iron and manganese. As a legume, they support digestive health and provide sustained energy. [source]

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Garden trellis cover & aesthetics

Household

The vigorous vines with attractive flowers and long pods make excellent living screens, arbor coverings, or ornamental garden elements. They provide vertical gardening solutions in small spaces. [source]

This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.

Harvest Tips

Begin harvesting when pods are 8-10 inches long and still tender, typically 8-12 days after flowering. Pods are best eaten at the tender stage before seeds mature and pods become tough and fibrous. Harvest every 2-3 days to encourage continuous flowering and production. Use a gentle twisting motion or scissors to avoid damaging vines. Peak harvest window is usually 3-4 weeks. Once pods mature fully and seeds begin enlarging, quality declines rapidly. Late-season mature pods can be dried for seed saving.

Fun Facts

🌱 Yard long beans are sometimes called 'snake beans' because of their long, sinuous pod shape, and they can grow to lengths of 12-18 inches or occasionally even longer if left on the vine.
🌱 These beans are actually a subspecies of the black-eyed pea (Vigna unguiculata) and have been cultivated in Asia for thousands of years, particularly in Thailand, India, and China.
🌱 Yard long beans tolerate extreme heat far better than traditional snap beans and actually produce better yields in hot, humid tropical climates, making them ideal for summer gardening in regions with intense heat.

Gardening Terms

New to gardening? Learn about terms used in this guide:

Full Sun Pollination Succession Planting Trellis True Leaves

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