Full-sized bulbing onions are the last of the major vegetable groups to plant and will produce their harvest in May. Non-bulbing onions such as scallions could have been started earlier in the year but large onions must wait until conditions are just right.
Onions require lengthening days in order to swell and produce the traditional onion shape. The winter solstice on 21st December is the shortest day of the year and your onion seeds should be in the ground by then. Make sure your seeds are labelled ‘short day’. Long day onions are used further north but we require short day onions. Some onion varieties are day neutral but these tend to be smaller types. The seed you buy from Pinewood Nursery have been specially selected for local gardeners.
You may wish to grow two varieties. Salad onions are mild and usually larger than yellow onions which are the ones which make your eyes water when you peel them and are great for cooking. White onions are of the salad type and are usually more expensive. Red onions are also mild and tend to be the sweetest of all.
Onions love sandy soil that has been enriched with compost. Exuma farmers have raised great onions for years using sand and seaweed. The seeds should be started in trays or a seed bed and, sown now, should be ready to transplant by the end of January. The slips should be planted out in rows with 5 to 6 inches between plants or in blocks the same distance apart. Plant the slips quite deep with a couple of inches of green leaf above ground. Onions need regular watering early on but less once the bases start to swell.
Onions send up tubular leaves and each leaf represents a layer of onion flesh. When onions reach full size the leaves wilt and dry. When fully dried the onions should be pulled from the ground, have the roots trimmed away, and left to cure for a week or so, turning them over daily.
Some onions are good keepers and store well; others need to be eaten within a month or so. Bunches of onions can have their dry leaves plaited and hung on hooks in an airy shaded position. If you are no good at plaiting you can trim and hang your onions in net bags and massage them every few days to ensure they each receive light and air. When you trim the foliage from your onions you should leave two inches of stalk. If you trim too closely the onions may rot. Once the onions are fully cured the stalks can be trimmed flush to look like supermarket produce.
Leeks are long non-bulbing onions that infuse soups and stews with their rich and distinctive flavour. They are little used in Bahamian cuisine and are very expensive compared with regular onions. Give them a try, however, for they are prized in many areas of the world. Allow the seedlings to stay in the seed bed until they are very well rooted and then transplant very deep. I like to add a ‘tea’ made from rainwater-soaked compost to leeks and other onions to give them a tonic.
Now is also the time to set out garlic and shallots. Individual garlic cloves should be buried two inches deep in rich sandy soil and kept fairly dry as too much water is detrimental. Only use perfect plump garlic cloves and leave the ‘skin’ on. Your garlic plants will take 5 or 6 months to mature but will are fairly maintenance free.
Shallots are grown the same way using individual divided bulbs. Make sowings once a month because shallots can last well into the summer.