Onion Growing Stages | How to Grow Them? Complete Step by Step Guide

Onions are eaten worldwide with significant demand in curries, salads, and soups. Let’s go through the stages of growing onions. Onion is a vegetable that you can quickly grow on land or in a pot.

Onions have shallow roots with hollow stems and leaves, so they need comparatively more draining and watering. Thus, they will get the best growth in soil that is drained well and organically rich. 

The best time to plant Onion bulbs is late fall or early winter. You can harvest them in the late spring season or early summer times.

The Stages of Onion Growth are as follows:

  1. Germination
  2. Seeding
  3. Vegetative Growth
  4. Bulb Formation
  5. Maturation
  6. Harvesting 

Germination happens when the seed sprouts and the shoot comes out.

Vegetative growth is the phase of the plant’s rapid growth with the production of green leaves and the formation of the white bulb. Bulb formation is when the plant discontinues growing, and the onion bulb only grows larger.

So, every stage is equally important and requires constant care for the plant. It is necessary to water regularly. Protection from infections and cold, dry weather is essential.

Steps to Growing an Onion Plant

Steps to Growing an Onion Plant

Let us see how easily we can grow onions with the help of these six steps.

1. Germination


It is the process of seed-producing or changing into a plant. Germination is the first and most crucial step in the growth of an onion plant. In this process, the seed dissolves the outer skin for the embryo to grow. After the embryo develops, it creates the root and shoot systems.

The roots develop downwards into the soil, and the shoot system grows upwards towards the surface and cooks food.

The time duration of a complete Onion Germination can vary from a few days to a few weeks. The amount of time taken for this variedly depends on aspects like temperature, humidity, and soil that it is growing in.

The germination happens faster on a large scale of temperature and humidity. On the other side, germination slows down in low temperatures and moisture—the soil matters as well in this process. 

Clay soils are not a very good choice for faster germination as they tend to be draining slowly and are usually saturated.

2. Seedling


The Onion Seedling is the stage known as the first step of the life cycle of an onion plant. Now the tiny onion seed turns into a green plant. It is indispensable to maintain good drainage in the seedling stage.

The plant grows continuously in this step. So keep regular watering and fertilizing for excellent and healthy growth. 

A good level of moisture and warm temperature – are the required conditions for a good sprout of the onion plant. So usually, in 10 to 14 days, the onion seed will adequately germinate and then grow into a tiny little green plant.

In this stage, the plant will reach its best height. If it grows fast, it will produce large and healthy onion bulbs. It is the only reason it is aptly necessary to provide abundant water and other nutrients in this stage. 

On the other side, if it is not supplied with enough water and nutrients, it will not get tall and produce smaller bulbs.

When it’s full with the bunch of the long green leaves, it’s all set for the next step, the Bulbing Stage.

3. Vegetative Stage

Vegetative Stage

It is the initial stage in the growth of the Onion Plant. This stage starts from the appearance of the seedlings from the soil, and it continues till the plant starts making the bulbs. 

In this stage, plants grow fast to develop their primary formation. Onion plants will require abundant watering and nutrients in this stage if you want them to have more significant and healthier growth. Lesser watering will reduce their growth.

On the other side, it is also vital to have proper spacing between the onion plants while the vegetative stage as they will require a lot of space to grow. If you plant them close together, they get stunted, and as a result, they will produce smaller onions.

The different types of onion plants have different durations of their vegetative stages. Some of the plants have the bulbs complete in some weeks, and others require a few months.

As the plants reach the vegetative stage, it becomes necessary to get them the right conditions for the best growth. It counts for water in many quantities, fertilizers, and enough sunlight.

So, feeding them with the right amount of water, nutrients, sunlight, and good soil becomes a critical task in this stage. It will help them in harvesting great crops.

4. Bulb Formation Stage

Bulb Formation Stage

After the onion plant reaches the bulb formation stage, it starts to make a small bulb on the top portion of its stem. It will keep growing until the harvesting time.

While this time, the onion plant will also make fresh onions below the soil’s surface. They will also keep growing until the time of harvesting.

One must note that every plant will not produce bulbs equally significant in size. Some plants might produce smaller bulbs multiple in size, whereas some plants may produce only one single bulb that is big enough. It solely depends on the varieties of the plants. It’s necessary to keep a watch tracking your plant in the bulb formation stage. 

You must be alert to check the harvesting time and harvest the crop on time; otherwise, they will get rotten.

5. Maturation Stage

Maturation Stage

The Onion Plant’s maturation begins at the end of the onion plant’s cycle when all the leaves have turned brown and pale. Before this, you will notice the onion greening when it enters its reproduction phase producing flowers on the stalk.

The onion maturation stage begins in a dry time that is usually hot and dry. Thus, the plant sheds its outer leaves to get lesser water loss. The maturation in the onion plant is fastened by reducing days as summer ends during this time.

Because of this, the bulb stores the plant’s carbohydrates at the cost of leaves. The top sides of the onions will turn into straws with a bit of purple dash and will fall over totally. It is the prime duration for Onions Maturation when the onion necks are well-shaped yet soft enough to blend easily without getting torn.

6. Harvesting Time 

Harvesting Time

When the Onions have reached the harvesting step, it’s the perfect time to harvest your ripe and matured onions.

Generally, there are many ways of the onion harvest. The most usual among them is by using a digging fork that makes the soil around the onions a little loose, and you can easily pull them out with your hands. It would be best if you were very careful in this process not to harm the onions and make perfect harvesting.

Another popular way is by using a spade or shovel. First, you chop off the leaves from the surface, then dig off the onions from below the soil.

You may choose any method from these, but you need to be careful while chopping that you leave enough stalks for onions to remain altogether. Once the harvest is complete, you need to cure them for 20-25 days. It makes the onion stay as rigid as required, and that makes it easier for you to store them well.


Onion is, in general, an excellent option for all kinds of diets. It promotes weight loss as well. It holds a lot of fiber, and that gives you better digestion. Onions can be stored for many months in good conditions, like keeping them in dry spaces in an open area.

Thus, Onions are a crop for cold seasons, which grows from a seed in spring and are harvested at the end of the summer. The best temperature scale for the best growth of onions is between 60 to 80 degrees F / 16 to 27 degrees C. every plant needs at least 6 to 7 hours of sunlight every day without any skips. 

In the United States, the onion plants can be grown and harvested. They get good growth in places where we get long and cool summers. So, start getting your crops by following the above steps and get a fabulous gardening experience while you will harvest your onions in your own homes and gardens.

About Jennifer Igra

Growing up in Brooklyn, New York City known for it’s green gardens. Jennifer, a 30 year old gardener and green living fanatic started Igra World to share her gardening journey and increase gardening awareness among masses. Follow Igra World to improve your gardening skills.

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