Green Onion
Allium Fistulosum
Allium fistulosum, commonly known as green onion or scallion, is a versatile and flavorful herb native to Asia. It is prized for its culinary uses and easy cultivation, making it a favorite among gardeners.
Everything it needs
9 essentials at a glance
Watering
Water Allium fistulosum regularly, ensuring the soil remains consistently moist but not waterlogged.
During the growing season, water every 1-2 weeks, adjusting frequency based on rainfall and temperature. Signs of over-watering include yellowing leaves and root rot, while under-watering may cause wilting and browning leaf tips.
Light
Allium fistulosum thrives in full sun, requiring at least 6-8 hours of direct sunlight daily.
Ideal placement includes a south-facing garden bed or a sunny windowsill. It can tolerate partial shade, but growth may be slower and less vigorous.
Soil
This plant prefers well-draining, loamy soil with a pH range of 6.0 to 7.0.
A recommended potting mix includes a combination of garden soil, compost, and sand to enhance drainage. Ensure the soil is rich in organic matter to support healthy growth.
Humidity
Allium fistulosum prefers moderate humidity levels, ideally around 40-60%.
To increase humidity, mist the plants or place a humidity tray filled with water nearby. Signs of low humidity stress include curling leaf tips and slow growth.
Temperature
The ideal temperature range for Allium fistulosum is between 60-75°F (15-24°C).
It is hardy in USDA zones 3-9, tolerating light frost but not extreme heat. During summer, provide some shade if temperatures exceed 85°F (29°C).
Fertilizing
Use a balanced fertilizer with an NPK ratio of 10-10-10, applying every 4-6 weeks during the growing season.
In fall, reduce feeding to once every 8 weeks. Signs of nutrient deficiency include stunted growth and yellowing leaves.
Pruning
Prune Allium fistulosum by trimming back any dead or damaged leaves as needed.
Use clean, sharp scissors or pruning shears. Deadheading is not necessary, but removing flower stalks can redirect energy to leaf growth.
Repotting
Repot Allium fistulosum every 2-3 years or when the plant becomes root-bound.
Choose a pot that is 1-2 inches larger in diameter. Signs it needs repotting include roots growing out of the drainage holes and stunted growth. To repot, gently remove the plant from its pot, loosen the roots, and place it in fresh soil.
Propagation
Allium fistulosum can be propagated through seeds or division.
For seeds, sow them directly in the garden in early spring, covering lightly with soil. For division, carefully separate established clumps in spring or fall, ensuring each division has roots and foliage. Replant immediately.
When it's unhappy
Yellow leaves
Why it happens
This can be caused by over-watering or nutrient deficiency.
How to fix it
Check the soil moisture and reduce watering frequency. Apply a balanced fertilizer if nutrient deficiency is suspected.
Wilting leaves
Why it happens
Wilting may indicate under-watering or extreme heat.
How to fix it
Increase watering frequency and provide shade during the hottest part of the day.
Root rot
Why it happens
Root rot is often caused by overly wet soil and poor drainage.
How to fix it
Ensure proper drainage and reduce watering. Remove affected roots and repot in fresh, dry soil.
Pests (e.g., aphids)
Why it happens
Aphids can infest the plant, especially in warm, dry conditions.
How to fix it
Use insecticidal soap or neem oil to treat infestations. Regularly inspect the plants for early signs of pests.
Slow growth
Why it happens
Slow growth can result from poor soil quality or insufficient light.
How to fix it
Improve soil quality with compost and ensure the plant receives adequate sunlight.
Care through the year
Spring
In spring, focus on planting seeds or dividing established plants. Ensure consistent moisture as temperatures rise.
Summer
During summer, provide adequate water and consider some shade during extreme heat. Regularly check for pests.
Fall
In fall, reduce watering and fertilizing as growth slows. Prepare for winter by mulching around the base to protect roots.
Winter
In winter, if grown indoors, maintain moderate humidity and avoid over-watering. If outdoors, protect from frost.
Toxicity & Safety
Allium fistulosum is non-toxic to pets and children. However, ingestion of large quantities may cause gastrointestinal upset. Symptoms include nausea and vomiting.
Good to know
How often should I water my Allium fistulosum?
Water your Allium fistulosum every 1-2 weeks, ensuring the soil remains consistently moist but not soggy. Adjust based on rainfall and temperature.
What is the best light for growing scallions?
Allium fistulosum thrives in full sun, requiring at least 6-8 hours of direct sunlight daily for optimal growth and flavor.
Can I grow Allium fistulosum indoors?
Yes, you can grow Allium fistulosum indoors as long as it receives sufficient sunlight, ideally placed near a south-facing window.
What soil type is best for Welsh onions?
Welsh onions prefer well-draining, loamy soil with a pH range of 6.0 to 7.0. A mix of garden soil, compost, and sand works well.
How do I propagate Allium fistulosum?
You can propagate Allium fistulosum through seeds or division. Sow seeds in early spring or divide established clumps in spring or fall.
Why are my scallion leaves curling?
Curling leaves may indicate low humidity or pest issues. Increase humidity levels and check for pests like aphids.
When should I fertilize my Allium fistulosum?
Fertilize every 4-6 weeks during the growing season with a balanced fertilizer. Reduce feeding in the fall.
Grows well with
Track this plant in your garden.
Set care reminders, log growth, and join a community of plant lovers.