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How to Grow Yard Long Bean 'Amusu Black Seed'

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Yard Long Bean 'Amusu Black Seed'

Vigna unguiculata subsp. sesquipedalis

vegetable

Yard long beans are vigorous climbing vines that produce exceptionally long, slender pods reaching 12-18 inches or more. 'Amusu Black Seed' is a dark-seeded variety prized for its tender pods, prolific production, and excellent flavor. This heat-loving crop thrives in warm climates and is a staple in Asian cuisines.

Looking for a specific variety?

Red Noodle Mosaic Purple Queen Bangkok Giant Black Seeded Golden

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Example Yard Long Bean 'Amusu Black Seed' timeline · Pittsburgh, PA (Zone 6b)

  1. Plant Yard Long Bean 'Amusu Black Seed'

    Around Apr 17

    Near Pittsburgh's average last spring frost.

  2. Tend & protect

    Late spring–summer

    Watering, feeding, and pest-watch reminders.

  3. Harvest Yard Long Bean 'Amusu Black Seed'

    Around Jun 16

    ≈ 60 days after planting

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

Growing Conditions

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Sun: Full sun, 6-8 hours daily minimum
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Water: Keep soil consistently moist but not waterlogged. Water deeply 1-2 times per week depending on temperature and rainfall. Increase frequency during hot weather and flowering/pod production. Mulch to retain moisture and regulate soil temperature.
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Spacing: 6 inches
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Days to maturity: 60-80 days
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Planting depth: 1

Soil

Type: Well-draining loamy to sandy loam soil
pH: 6.0-7.0
Amendments:
Compost Aged manure Perlite or sand for drainage

Growing Zones

Find your zone →

Thrives in zones 9-11; grows as annual in zones 6-8 with proper timing

9a 9b 10a 10b 11a 11b

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Growth Stages

1

Seedling

2-3 weeks

Cotyledons emerge within 7-10 days. First true leaves appear as small, simple leaflets. Plant is low-growing and vulnerable.

Keep soil warm (70-85°F) and consistently moist. Provide bright light. Protect from wind and cold. Thin seedlings to proper spacing once established.

2

Vegetative Growth

3-4 weeks

Plant develops trailing or climbing vine structure with compound leaves. Stems become woody and strong. Tendrils form for climbing support.

Provide sturdy trellis, pole, or support structure immediately. Water regularly and fertilize every 2-3 weeks with balanced fertilizer. Maintain warm temperatures (75-85°F). Remove any diseased or weak growth.

3

Flowering

3-5 weeks into continuous production

Purple, pink, or white flowers bloom along the vine in clusters. Flowers are delicate and appear continuously throughout the season.

Maintain consistent watering and warmth. Pollination is generally self-fertile and aided by bees. Continue light fertilization with balanced or slightly higher phosphorus formula. Do not allow vine to dry out during flowering.

4

Pod Development & Maturation

7-14 days per pod batch; continuous throughout season

Long, slender pods develop from flowers, elongating to 12-18 inches. Pods are tender and green at edible stage, with smooth skin. Seeds inside are black (characteristic of 'Amusu Black Seed').

Harvest pods regularly when young and tender (6-10 inches) to encourage continued production. Water consistently—stress can cause pod drop or stringiness. Fertilize with potassium-rich formula to support pod production.

5

Late Season / Full Maturity

Extends until frost

If left unharvested, pods mature fully, become longer and tougher, and seeds inside harden and develop full black color. Plant continues producing until frost.

Allow some pods to mature if saving seeds. Continue harvesting young pods for best table quality. As temperatures cool in fall, production slows. Plan for season end before first frost.

Companion Planting

Plan your garden →

Plant with:

Corn Squash Cucumber Basil Marigold Nasturtium Radish

Avoid planting near:

Fennel Onion Garlic Brassicas (cabbage, broccoli)

Common Pests

  • Hand-pick adults and larvae. Use neem oil or spinosad spray. Plant resistant varieties. Rotate crops yearly.

  • Increase humidity and water misting. Use sulfur dust or neem oil. Remove heavily infested foliage. Encourage predatory mites.

  • Use yellow sticky traps. Spray with neem oil or insecticidal soap. Maintain good air circulation. Remove infested leaves.

  • Spray with strong water stream to dislodge. Use neem oil or insecticidal soap. Encourage beneficial insects like ladybugs and lacewings.

  • Ensure good air circulation and avoid overhead watering. Apply sulfur dust or baking soda spray (1 tbsp baking soda + 1 tbsp oil + 1 tsp soap per gallon). Remove affected foliage.

Uses

🍳

Tender pod cooking

Culinary

Young yard long bean pods are prized in Asian cuisine, especially Thai, Vietnamese, and Chinese cooking. They are stir-fried, steamed, or boiled and have a slightly sweet, tender flavor and unique elongated form. [source]

🍳

Dried bean harvest

Culinary

Mature black seeds can be cooked as dried beans, similar to black-eyed peas, providing protein and fiber. They store well and are nutritious. [source]

🏠

Nitrogen fixation

Household

Like all legumes, yard long beans fix atmospheric nitrogen through root nodules, enriching soil and reducing the need for synthetic nitrogen fertilizers in subsequent plantings. [source]

🦋

Pollinator support

Wildlife

The flowers attract bees and other beneficial insects, providing nectar and pollen sources during the growing season. This supports local pollinator populations. [source]

🍳

Nutritional benefits

Culinary

Yard long bean pods are rich in vitamins A, C, and K, as well as folate and fiber. The beans contain plant-based protein and essential minerals like iron and potassium. [source]

Harvest Tips

Harvest pods when young and tender, typically 6-10 inches long, before they become stringy and tough. Pods should snap cleanly when bent. Pick every 2-3 days to encourage continuous flowering and production. Early morning harvest yields the crispest pods. For seed saving, allow several pods to mature fully on the vine before the first frost; harvest mature pods and dry them completely before extracting black seeds. Seeds can be stored for 3-5 years.

Fun Facts

  • 🌱 Yard long beans can grow to 18+ inches in ideal conditions, earning them the name 'asparagus bean' in some regions because of their unique elongated form and tender texture.
  • 🌱 'Amusu Black Seed' is particularly popular in West African and South Asian cuisines and the black seeds are distinctive, making saved seeds easy to identify and replant.
  • 🌱 Yard long beans are more heat-tolerant and drought-resistant than common snap beans, making them an excellent choice for hot summer gardens where regular beans struggle.

Gardening Terms

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

Full Sun Mulch pH Pollination Trellis True Leaves
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