Evaluation of onion spacing on yield

Introduction Onion production in many western states use plant populations in excess of 100,000 plants per acre, which can result in yields of 2,000 50-lb bags per acre or more. This is possible because of larger equipment (wider wheel spacing), which facilitates more plants per acre as well as more closely spaced rows. In some cases where onions are to be used for dehydration, shear tonnage is all that matters. In addition, with weather conditions generally dryer, closer spacing is possible without the concern of increased disease. Although southeast Georgia does have high rainfall and humidity, which increases disease pressure along with the production of sweet onions which are more susceptible to diseases, with the advent of better disease control products it may be possible to increase plant population without adverse problems. In addition, because Vidalia onions are grown under center-pivot systems, growers generally grow onions behind onions increasing soil borne disease pressure. They cannot rotate their crops because of this limitation. Increasing plant populations may allow them to incorporate crop rotation and/or allow fields to lay fallow and recover from continuous cropping. This experiment was to evaluate different plant spacings and its effect on yield.