Onions come in three general colours—white, yellow, and red/purple—each with their own distinct taste. Yellow onions are golden with a slightly sweet flavour, white onions are sharp and a bit tangier than their yellow counterparts while red onions are violet and are often eaten fresh rather than cooked.
2. How to plant: There are two popular ways—using either onion sets (bulbs) or seeds. Gardeners tend to prefer planting onion sets, as they are hardier and can withstand poor weather better than seeds. The other option is to grow the vegetable from transplants/cuttings, but this will you give optimum yields.
3. When to grow: Onions must planted at the right time. If planted in cold weather, they can die off or waste energy in blossoms rather than bulbs. Always start off from the nursery to ensure you control the timing for transplanting to the field.
4. Select site: Onions aren’t too terribly picky when it comes to growing conditions, but they do have some preferences.
Select a place with plenty of room and full sunlight. Onions will grow quite large if they’re given enough space. Avoid planting them in a location that is shaded by larger plants or trees. Remember, onions grow well in raised beds.
5. Preparing the soil: Prepare your plot for planting several months in advance for better yields. Add adequate manure besides testing the pH level— should be between 6 and 7.5— of your soil.
When you’re ready to plant, till the soil about 6 inches (15.2 cm) deep and add a layer (1 cup per 20 feet) of phosphorous fertiliser. Using a mixture such as 10-20-10 or 0-20-0 will provide an extra boost for your developing onions.
6. Digging the holes: Plant onions so that no more than one inch of soil is placed above the sets or seedlings. Space onion sets 4–6 inches (10.2–15.2cm) apart, and onion seeds 1–2 inches (2.5–5.1cm) apart. As your onions begin to grow, you can transplant them and space them further apart in order to increase their growing size.
7. Planting: Place your seeds in the holes you’ve dug, covering them with ½ to 1 inch (2.5cm) of soil. Use your hands or shoes to firmly tamp the soil over the top of the onions; they grow better in firm, rather than loose, soil. Finish up planting by adding a bit of water, and you’re set to watch them grow!