Onions can indeed be grown for two years. In fact, onions and their close relative, leeks, are biennial plants. This means that they typically take two full years to complete their life cycle, from seed to flower to setting seed again.
The first year of an onion’s growth is dedicated to what is called the vegetative stage. During this time, the onion focuses on developing its root system, leaves, and other above-ground growth. This is the stage where the onion bulb starts to form and expand underground. It’s fascinating to watch as the onion grows larger and its green stems shoot up towards the sky!
As the first year comes to an end, the onion enters a dormant period during the winter months. This is when it hunkers down and prepares itself for the next stage of its life cycle. When spring arrives, the onion will start to grow again, but this time with a different purpose in mind.
In the second year, the onion transitions into the reproductive stage. It sends up a tall flower stalk, known as a scape, which eventually produces small, bulb-like structures called bulbils. These bulbils contain the onion’s seeds and are responsible for perpetuating its species. However, it’s worth noting that not all onion varieties produce bulbils. Some may produce flowers and seeds directly on the flower stalk.
Once the onion has completed its reproductive stage and the seeds or bulbils have matured, the plant will naturally start to wither and die. At this point, you can harvest the onion bulbs and save them for future use or replant them to continue the cycle.
While it is possible to keep onions for longer than two years, they are typically grown as annuals or biennials. This is because onions are best harvested and consumed when the bulbs are still young and tender, which is typically around the end of the first or second year.
To sum it up, onions and leeks are fascinating biennial plants that require two years to complete their life cycle. They spend the first year developing their vegetative growth, including the bulb that we commonly consume. In the second year, they shift their focus towards reproduction, producing flowers, seeds, or bulbils. So, if you have the patience and space, growing onions for two years can be a rewarding experience in your garden.
