Agri Facts and Tips: Onions
General:
Onions can be grown in all parishes in Jamaica.
• For commercial production, the crop thrives best in full sunlight, in medium-texture soils.
• Land should be flat and chosen site should allow for good wind circulation.
Time of planting:
• Onions are classified as short, intermediate or long-day types, which reflect the hours of sunlight that will trigger bulb formation.
• The day length for short, intermediate and long days is less than 12, 12-14 and greater than 14 hours, respectively.
• Only short and intermediate onions are grown in Jamaica as the country’s daily sunshine period does not exceed 14 hours.
• Between March 12 and September 26, the country’s average monthly sunshine lasts 12.7 hours and the onions best suited for this period are the intermediate types.
• The short-day onions will produce better between September 27 and March 11, with a mean of 11.5 sunshine hours.
Varieties:
• The Mercedes, Arad, Superex and the Grano type onions are recommended for cultivating between mid-October and December.
• For the months of March and April Orlando, Caballero, Yellow Granex Hybrid and Noam are the varieties which will produce good yields.
Crop Nutrition and Irrigation:
• The important nutrients for onion production are nitrogen, phosphorus, potassium, sulphur, manganese, copper, and molybdenum.
• Prior to any fertiliser application, a soil analysis must be done in order to determine soil texture, organic matter, soil compaction and nutrient availability.
• Onions require approximately 500,000 gallons of water for growth and development per crop cycle, which is 110 days.
• The critical stages at which moisture stress is to be avoided are at the germination and bulbing stages.
• Sprinkler, drip and furrow irrigation methods may be used in onion production.
Weed control:
• Weed control is very important as onions are slow-growing and cannot tolerate weeds at the early stages of their development.
• Use herbicides that are effective against weeds and can be safely applied to the onions such as Nabu-S.
• The application of plastic or organic mulch, such as guinea grass, is also useful.
– Source: Grow Jamaica: A Ministry of Agriculture technical guide series