How to Grow Green Onions: A Comprehensive Guide for Gardeners in Arizona and Beyond
Green onions, also known as scallions or bunching onions, are a delight to grow. They’re versatile, easy-to-care-for plants that add a punch of flavor to any dish. While all onions can be harvested early and enjoyed as scallions, green onions have a milder flavor than their mature counterparts, making them an excellent choice for those who prefer a gentler taste.
If you’re wondering how to grow green onions, especially in hot summer climates like Arizona’s, I’ve got you covered with this comprehensive guide.
Varieties to Try
Two easy-to-grow varieties worth considering:
- Tokyo Long White Bunching Scallion Onion Seeds: Known for their long, slender shape and mild flavor.
- White Lisbon Bunching Scallion Onion Seeds: These are quick-growing, compact onions that are perfect for small gardens or containers.
Planting Green Onions
If you live in a hot climate, plant green onions outside starting in the fall when temperatures start to cool. For example, in Arizona, it’s best to wait to plant scallion seeds outdoors from September 15th until April.
In other areas, plant green onions 4 to 6 weeks before the average last frost date or when the soil temperature reaches 45°F (7°C), ideally 60°–85°F (15°–29°C). For continuous production, consider planting every 2 to 4 weeks.
Plant seeds ¼ inch deep (0.64 cm), with a spacing of 1/2 inch (1.27 cm). Thinning is not necessary unless larger onions are desired.
Location, Soil, and Sunlight
Green onions prefer friable, well-draining soil with a pH of 6.2–6.8. They need at least 6 hours of sunlight daily. If you’re using the square-foot gardening method, aim for 16 plants per square foot.
Excellent companion plants for green onions include spinach and strawberries.
Caring for Green Onions
Green onions are easy to grow and care for. Ensure they have even, constant moisture, and don’t let them dry out. Mulching helps maintain soil moisture. They generally don’t require additional fertilizer and are usually pest and disease-free.
Growing Green Onions in Containers
If you’re short on space, green onions do well in containers. Ensure your container is at least 6 inches (15 cm) deep.
Harvesting Green Onions
You can harvest green onions at any stage, but they’re usually ready when they reach 6-8 inches (15-20 cm) tall. Clip plants about an inch above the soil surface for repeated harvests, and they will regrow. To grow bulbs, harvest entire plants, leaving 3″-4″ (7.62 cm – 10.16 cm) of space between remaining plants.
Using and Storing Green Onions
For the best results, use green onions quickly after harvesting. Store them with roots in water, and they’ll last about a week. You can also chop and freeze them. The entire onion is edible. Replant the roots to grow more onions!
Tips for Growing Green Onions in Hot Climates
Growing green onions in Arizona’s low desert (or other hot climates) may require extra care. Provide shade if growing during warm months to extend the season, prevent bolting, and encourage germination. Plant seeds a little deeper if temperatures are still warm outside.
Learn how to grow I’itoi onions and bulbing onions in these blog posts: