Home Garden Green Bunch Onions

Revised 1/01 -- Author Reviewed 1/01 HIL-8018

Douglas C. Sanders
Extension Horticultural Specialist
Department of Horticultural Science
College of Agriculture & Life Sciences
North Carolina State University

 

When onions are harvested in the green or immature stage they are called "green bunch onions." These onions are sold in bunches tied with a rubber band. This is a popular crop for home and market gardeners in the fall, winter and early spring. Acreages are usually small because of the amount of hand labor required for planting and preparation for market.

Soils -- Any fertile, well-drained soil is suitable for bunch onions. Since this is a shallow rooted crop, soils high in organic matter give much better results, unless irrigation is available. Soil pH should be 6.0 to 6.5.

Varieties

Fertilizer -- Apply 2 to 3 lb of 10-10-10 per 100 ft2 7 to 10 days before planting. Sidedress with 3 to 4 oz of nitrogen three weeks after plant emergence and every 3 weeks for 3 total applications.

Spacing -- Plant on beds 4 to 6 inches high for good drainage. Row spacing can be 2 rows per bed on 38 inch centers or 4 rows per bed on 60 to 76 inch centers. If 2 rows per bed are used space rows 9 to 12 inches apart (allow room for cultivation between rows). If 4 rows per bed are used space rows 9 to 18 inches apart. For sets or seed, spacing in the row should be 1 to 2 inches. Transplants should be spaced 2 to 4 inches in the row.

How to Plant -- One of four general methods may be used. They are listed in order of easy stand establishment.

  1. Plant sets (about 3/4-inch in diameter) any time from September through February. The larger the sets, the sooner the green onions are of desired size. Large sets tend to form seed stalks earlier than smaller sets. In the early fall and late winter, onions can be produced in 6 to 8 weeks.
  2. Plant seed in protected beds in September and set in the garden when plants are about 6 inches tall. Seed 12 to 18 seeds per ft of row, in rows 4 to 6 inches apart. It takes about 4 to 6 weeks for the plants to get large enough to set and then an additional 6 to 10 weeks for desired size plants.
  3. Seed directly in the garden in late winter and then thin to proper stand when plants are 2 to 3 inches high. This method is not used for fall or early winter harvest. It will take 12 to 18 weeks to produce a crop, depending on how frequently you fertilize and irrigate.
  4. Buy plants for setting anytime from September through March. This method is used primarily by gardeners for winter and spring onions.

Weed Control* -- Cultivate shallow; only enough to control weeds. Two to 3 weeks before harvest approximately two inches of soil should be worked around the base of the stem. This is known as blanching and results in onions that have a longer "white and tender" stem.

Disease Control* -- Downy mildew can be a problem in late spring and summer crops. Use a good fungicide for control of diseases.

Insect Control* -- Thrips are a common pest of onions and should be controlled.

Harvesting -- Harvesting usually begins in late fall and continues to late spring. When the white bulbs are one-half to one inch in diameter the onions can be harvested. Loosen onions with a fork before harvest. Pull off the discolored outside skin leaving the basal part of the plant white and clean. The quality and color of green onions deteriorates very rapidly, thus the onions should be harvested shortly before use. During the late spring and early summer, many onions are pulled when the bulb is about the size of a half dollar piece, the roots and tops trimmed, then they can be used as "stewing onions".

General -- Bunching onions respond to irrigation and fertilizer. The most successful gardeners manage both of these factors to keep onions growing rapidly. By "pushing" this crop the crop matures more rapidly and a gardener can get more from a unit of land.

Forcing -- Some gardeners get rapid growth with uninjured tops by planting onion sets in protected beds. Protection may consist of anything from a hedge row or building as a windbreak, to covered coldframes or even plastic greenhouses. When onions are "forced" in such beds, they are often mulched with straw, sawdust or other organic material to reduce weed growth since they are planted very close together (about 3 x 3 inches) and cultivation would be difficult.

* For information on pest control, consult your county Extension agent or the current issue of the NCCVR (North Carolina Commercial Vegetable Recommendations, AG-586) .


Recommendations for the use of chemicals are included in this publication as a convenience to the reader. The use of brand names and any mention or listing of commercial products or services in this publication does not imply endorsement by the North Carolina Cooperative Extension Service nor discrimination against similar products or services not mentioned. Individuals who use chemicals are responsible for ensuring that the intended use complies with current regulations and conforms to the product label. Be sure to obtain current information about usage and examine a current product label before applying any chemical. For assistance, contact an agent of the North Carolina Cooperative Extension Service in your county.

Published by the North Carolina Cooperative Extension Service


Distributed in furtherance of the Acts of Congress of May 8 and June 30, 1914. Employment and program opportunities are offered to all people regardless of race, color, national origin, sex, age, or disability. North Carolina State University at Raleigh, North Carolina A&T State University, U.S. Department of Agriculture, and local governments cooperating.