Green Bunching Onions
by Master Gardener Joe Michalek
Green bunching onions are known by several names such as scallions, green onions, salad onions or spring onions. They are in the Alliaceae family which includes sweet onions, chives, shallots, leeks and garlic. This is a very diverse family with over 700 different types of onions from which to choose.
The common forms of bunching onions – those forming small bulbs – are Allium cepa. The nonbulbing types are A. fistulosum and include Welsh onions and the preferred Japanese bunching onions. Both are grown for their green tops but it is A. cepa that typically is found in grocery stores and farmers’ markets. The California Master Gardener Handbook lists the best quality varieties as ‘White Lisbon,’ ‘White Sweet Spanish,’ ‘Southport White,’ ‘Tokyo Long White’ and ‘Evergreen White.’ I am a seed saver when the opportunity presents itself. I’ve been saving seed from ‘Evergreen White’ with very good results for years. They grow very well in our county and winter over to make a year-round product available in the garden.
Growing bunching onions is relatively simple. In Sonoma County, they can be planted from March through October allowing for a continuous harvest if you stagger plantings. Expect 70 to 80 days to harvest. Place transplants two inches apart in rows separated by twelve inches. Alternatively, direct seed close together when the soil warms in the spring and harvest by thinning onions until they reach one-fourth to one-half inch in diameter. I do not direct seed as I find that I get better results from starting the seeds in a 4 inch
plastic container. When it is time to transplant the seedlings I knock them out of the pot and plant them in a furrow about two inches deep. While bunching onions prefer a soil that is slightly acidic, they thrive in any well-drained Sonoma County soil. They also can be grown in outdoor or indoor containers. If grown indoors, place them close to a window so that they do not get too leggy.
Bunching onions are heavy nitrogen feeders. Do not skimp here as the plants will not grow well without adequate nourishment throughout the growing season. They also need regular water for the overall growth of the plant. If your soil is not loose enough to hand pull weeds, take your hoe with you to the garden to keep the soil around the onions weed free. But, do not disturb the shallow roots which fan out in a six inch diameter around each plant. This is a good plant to be included in the crop rotation as they are not carriers of the same diseases which affect other vegetables. Onions appear to be deer and rodent resistant as these creatures do not like the sulfurous taste of the tops. Silvery-white streaks or blotches on the leaves during dry, warm weather are evidence of thrips which can be sprayed with insecticidal soap.
Bunching onions are biennials. Eat them the first year and into the spring of the next year. During the second year, they set flowers at the head of each stalk. Because all of the plant’s energy is put into seed production, the plant loses its good flavor. After the seeds have matured in the spring they can be harvested and planted into pots and germinated so that they are ready for spring planting. Or, wait until the garden soil warms up in the spring and directly sow seed.
There is no need to remove onions when you clear out the fall garden. They will survive the winter and be edible until they set flowers in the early spring. If you want to transplant the scallions to another location in the garden or to a raised bed, be sure to cut the roots about half of their original length prior to transplanting. The cutting of the roots gives the plant a chance to regenerate the roots and makes a stronger plant for the winter.
The health benefits of this plant family are many. There are only 47 calories in a one-half cup serving of bunching onions. Primary nutrients are vitamin C and folic acid. The University of California Cooperative Extension Center for Health and Nutrition Research reports that onions contain flavonoids (specifically, quercetin). Research suggests that flavonoids may be an important phytochemical group that contributes to the reduced risk of chronic disease – with onions contributing to a decrease in LDL cholesterol which is the bad cholesterol. Also, quercetin is an anti-inflammatory and has antioxidant properties.
Enjoy growing and eating this delicious Allium in its many forms on your table.