Pro-Organic Belize Grow Guide
Where you are the student and the teacher
Plant of the Month - September 2025
Onions
by Mary Loan

Onions, known by their botanic name, Allium cepa, a biennial root, are one of the most widely cultivated crops world-wide.  According to archaeology research, onions have been grown in all but the coldest zones of planet earth for over 7,000  years.  It is believed that onion cultivation originated in central Asia and spread over the world. India is the highest producer of onions on earth.

 

There are hundreds of varieties of onions. For this article we feature common yellow, white and red onion varieties that can be grown in tropical countries like Belize. 

 

If you have a garden area in your backyard or garden with loamy well drained soil that gets at least eight hours a day of full sunlight and someone to weed, water and watch for garden pests, you are on your way to planting, growing, harvesting, eating and storing onions.

 

Onions are grown in three different ways: by seeds, plugs (which are green onion shoots) or by planting onion sets which are immature bulbs grown from seed planted the previous year.  It is said the best size to plant the onion sets is when the bulbs are about the size of a Belizean nickel.  Here is how it is done:  first determine what method you choose to plant onions, next procure seeds, onion plugs, or onion sets from agricultural suppliers.  Crescent Garden Nursery in Belize City, Jiron Farm and Supply Company in Spanish Lookout, or The Seed Agent in Benque Viejo are good sources.  Seeds are the least expensive method with the most amount of work; next is onion plugs, with onion sets being the easiest. Planting by seeds requires an area completely weeded and cultivated.  Seeds are planted about ½ inch deep in trenches and thinned to about 3 inches apart.  The thinned greens can be cooked or sprinkled on a salad. Onion plugs are planted about 3 inches apart with the base of the plug planted just below the soil line and greens left attached. Onion sets are planted 1 inch deep and 3 inches apart.   For all three methods, leave about 18 inches between rows.  Be sure to water daily while the seeds are sprouting to keep the soil moist, then water when the soil dries out. Be sure to weed and mulch as the plants grow.  Seed grown onions are ready for harvest in about 130 days, seeds from plugs from about 110 to 130 days; those grown by sets generally mature in about 100 days.  Onion greens turn dry and brownish and the tops of the onion bulbs protrude from the soil when they are ready to harvest.  Once harvested, cut off the brownish tops, then allow the onions to dry for approximately two weeks, then store in a cool, dry and dark ventilated space.

 

Fortunately onions are vigorous plants; however they are susceptible to many garden pests and diseases.  Radishes inter-planted between rows of onions help to control onion root maggot damage.  Thrips are managed by the use of neem oil spray.  It is advised to destroy heavily infested onions and not add them to the compost as they will likely spread to other plants.

 

An onion a day helps promote good cardiac health and regulates blood sugar; an onion is an effective antihistamine, contains vitamin C and B6, and Omega 3, and is rich in sulfuric compounds.  Onions, especially red onions, also are a rich source of quercetin, which is a potent antioxidant flavonoid. 

 

The aroma of an onion sauteing at mealtime provokes the comment “Something smells good.....”

Onions are an ingredient in many recipes, from soups to stir fried veggies, salads, breads, confits and are a versatile ingredient raw and/or cooked.

 

Here is a simple recipe for an onion topping for sandwiches, potato or pasta salad, tacos or salad.

 

Onion Relish

 

4 medium sized onions, (red, yellow or white) thinly sliced

3 cloves garlic minced

1 TBS brown sugar

1 good pinch of salt (approx. 1/8 tsp.)

½ cup apple cider or red wine vinegar

½ cup water

about 10 whole peppercorns

 

Place sliced onions and garlic in a one quart jar, add the peppercorns, sprinkle with sugar and the pinch of salt, pour the vinegar and water over the onions, garlic, sugar and salt mixture. Shake the jar gently,

allow to marinate for a few hours, store in refrigerator