How to grow onions is simple and there are a number of onion varieties to choose from. You can purchase onions that are sold as seedlings or you can grow them from seeds. A more expensive option is purchasing adult plants sold in biodegradable pots. The most popular option for how to grow onions is sweet onions. This is a mild, sweet variety that offers more versatile cooking options. A good choice for sweet onion varieties includes Walla Walla or Texas Sweet.
How to Grow Onions: The Planting Process
If you’ve purchased seedlings, get your plants growing strong by using an organic or time released fertilizer. The fertilizer should be placed in the ground, below the planting furrow and before you plant the onions. This will place the nutrients in the soil right where the onion roots will find them. The roots will use the nutrient supply during the growing process.
How to grow onions is best done in good draining soil, with a soil pH that ranges from 6 to 6.8. Before you place the fertilizer into the planting furrows, add a two inch layer of compost. Set the plants two inches deep for seeds and for inches deep for seedlings so that the roots are well covered but the top of the neck is not buried too deeply. Burying the plant too deeply will cause the young leaves to rot. If you’re purchasing adult plants, bury them deep enough to completely cover the biodegradable pots.
Each plant should be spaced six inches apart. Each furrow should be about one foot apart. After planting, add a liquid fertilizer.
The root systems on onions are shallow, making them inefficient when it comes to sucking up moisture, so they’ll need a steady supply of water. Because of the shallow root system, this type of plant is also in danger of being overwatered. When watering, only do so long enough to soak the ground. The soil should be kept moist at all times, but do not flood the area. If the onion plants sit in water, the roots will begin to rot. An onion will naturally push towards the surface as the bulbs form. As they grow, remove any mulch that might keep the bulbs too moist.
Young onions can be harvested just a few weeks after planting. Young onions can be used as scallions or spring onions. You can harvest the onions based on your size preference.
Harvesting Mature Onions
How to grow onions with large bulbs will just involve waiting a longer period of time and harvesting once the tops turn yellow and fall over. When harvesting mature bulbs, pull them up and shake off the excess soil. You can lay them out to cure with the tops attached. The roots will shrivel as the onions cure and the necks will slowly dry up. After one week you can clip off the tops and roots. Be sure to remove as much dirt as possible without removing the outer skin. Store the onions in a cool dry place.