How to Grow Welsh Onion Tokyo Long Green
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Welsh Onion Tokyo Long Green
Allium fistulosum 'Tokyo Long Green'
vegetableTokyo Long Green is a Japanese bunching onion (Welsh onion) variety prized for its long, slender, tender green stalks and mild flavor. Unlike bulbing onions, it produces clusters of thin, elongated scallions ideal for fresh use and Asian cooking. This heirloom variety is highly productive and can be harvested continuously throughout the growing season.
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Example Welsh Onion Tokyo Long Green timeline · Pittsburgh, PA (Zone 6b)
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Plant Welsh Onion Tokyo Long Green
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 Welsh Onion Tokyo Long Green
Around Jun 16≈ 60 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Welsh Onion Tokyo Long Green dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 3-9; particularly well-suited to zones 5-8
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Get my Welsh Onion Tokyo Long Green timeline →Growth Stages
Seedling
2-3 weeksTiny thread-like shoots emerge; first true leaves appear thin and tubular
Keep soil consistently moist. Provide bright light if growing indoors. Thin seedlings to proper spacing once they have 2-3 true leaves.
Vegetative Growth
4-6 weeksMultiple slender green stalks develop from the base, forming dense clusters; plants are tender and flavorful
Maintain consistent watering and apply balanced fertilizer every 3-4 weeks. Remove any flowering stems if harvesting for greens. Mulch around base.
Leaf Development & Elongation
3-4 weeksLong, tender green shoots extend 10-14 inches; white basal portions develop; clusters thicken with multiple shoots per plant
Continue regular watering and feeding. Side-dress with compost or balanced fertilizer. Harvest outer leaves to encourage continued growth.
Harvestable Maturity
Ongoing (4-8+ weeks)Stalks reach 10-16 inches with tender whites and mild greens; plants are full, productive clusters ready for cutting
Begin selective harvesting of outer stalks. Remove any flower buds to redirect energy to leaf production. Continue watering and fertilizing.
Bolting (Optional)
2-3 weeks until bloomIf left unharvested or in long day length, plants produce tall flower stalks with white or pale pink umbels
Remove flower stalks if fresh eating is priority. Allow to flower for seed saving or as ornamental/pollinator support.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Use floating row covers over young plants; employ parasitic wasps; apply neem oil; practice crop rotation; remove affected plants immediately
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Use reflective mulches; spray with neem oil or insecticidal soap; encourage predatory insects; increase air circulation
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Ensure excellent drainage; avoid overhead watering; practice crop rotation; remove infected plants; use disease-resistant seed if available
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Handpick; use copper tape or diatomaceous earth barriers; encourage ground beetles; mulch with rough materials; beer traps
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Spray with strong water jet; apply neem oil or insecticidal soap; introduce ladybugs; plant companion flowers to attract beneficials
Uses
Fresh Asian Cooking & Garnish
CulinaryTokyo Long Green's tender stalks and mild onion flavor are essential in Japanese, Chinese, and Thai cuisine. Use fresh in stir-fries, soups, noodle dishes, and as a garnish for depth without harshness. [source]
Raw in Salads & Salsas
CulinarySlice thinly and use raw for a delicate onion flavor in salads, salsas, and ceviches. The white portions are especially tender and crunchy when eaten fresh. [source]
Grilled & Roasted Vegetable Side
CulinaryGrill whole stalks as a tender side dish or roast with olive oil until charred and caramelized. Their long shape makes them ideal for skewering and grilling intact. [source]
Traditional Herbal Remedy
MedicinalWelsh onions contain allicin and other sulfur compounds with antimicrobial and anti-inflammatory properties. Traditionally used in herbal medicine for immune support and respiratory health. [source]
Organic Pest Deterrent
HouseholdPlant near vegetables as a natural pest deterrent; the sulfur compounds repel some insects. Can be brewed as a weak spray for mild pest control on adjacent plants. [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 stalks are 6-8 inches tall by cutting outer leaves 1-2 inches above soil line; inner leaves continue growing. For mature bunches (10-16 inches), harvest by pulling entire plant or cutting at base. Successive plantings every 2-3 weeks provide continuous harvest. Early morning harvest yields tenderest, crispest stalks. Can be harvested multiple times from same plant over 8+ weeks.
Fun Facts
- 🌱 Despite the name 'Welsh Onion,' this plant likely originated in Siberia and was introduced to Europe via the Middle East; the etymology of 'Welsh' may derive from German 'welsch' (foreign) rather than Wales itself.
- 🌱 Tokyo Long Green is a Japanese heirloom prized for producing extra-long, tender stalks—some reaching 16+ inches—compared to other bunching onion varieties, making it especially valued in Asian markets.
- 🌱 Unlike bulbing onions, Welsh onions and scallions are perpetual if left in the ground in mild climates; they can regrow after harvesting for multiple seasons, and some gardeners maintain productive patches for years.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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