Onion Growing Stages | The Lifecycle of Onions

Every gardener wants to grow onions from seeds but no nothings about about onion growing stages. Before even thinking about growing onion, you need to have some knowledge about stages of onion growth to get successful and maximum onion yields.

Like other Amaryllidaceae plants, onions also have growing stages that start from germination and finish with collecting seeds for the future. Each of these stages needs proper care with specific conditions. You have to know each stage to get a bountiful harvest each time.

I have explained each of the growth stages of onions in the below guide along with its growing process in which I also share my expertise . So, let’s hop into it.

Growing Stages of Onions:

Onion is one of the most like vegetables that is used in almost every kitchen. Just like other plants, it has certain growing stages that, as a gardener, you should know if you want to plant them. If you don’t know, then don’t worry. I have a detailed blog that discusses the whole onion cycle very briefly, so without wasting any time, let’s get to it.

Seed Germination:

Germination is the first growth stage of every other plant, including onion. You might know what is germination but if not then let me tell you what it is in term of onions.

Germination is the process in which the seed develops into a seedling by developing and growing a sprout. It is considered the base stage of growth; if it goes properly, your future plant will be very healthy. For successful germination, keep the temperature about 65 to 80 F (17 to 28 C). It also needs proper, well-drained soil, consistent watering, and proper light. The timeframe for onion seeding is about 10 to 15 days.

Seedling Development:

In the life cycle of onions, the next stage is seedling development, in which you will see the first set of leaves of the onion plant. In this growth stage, you need to take proper care of your onion plant, and fulfilling its nutrient nutrient needs is a top priority. In this stage, nitrogen is needed the most to support and increase the leaf’s development. But you have to provide it in limited quality, so you need to dilute the nitrogen fertilizer and give it limited quality.

Related: Passion Fruit Growth Stages.

Common Challenges:

Seedlings are very vulnerable to issues like fungal disease and damping off, which can have the power to kill your plant. So you need to protect you plant against it by avoid overwatering, and make sure it get enough air.

Bulb Formation:

The bulb formation is the next stage of the life cycle of an onion. In this step, the onion focuses on growing its leaves and forming a bulb in its roots. It start storing nutrient in its bulb for future.

Factor Influencing Bulb Size:

Different factors affect onions’ bulb growth, and you need to manage those accordingly. It includes temperature, watering, and spacing. Onion belongs to photoperiodic family which required proper amount of sunlight so you need make sure it get that. In short day onion plants required 10 to 12 hours of sunlight, intermediate day, onion plants needs 12 to 14 hours of sunlight, and in long day onion plants needs about 16 hours of sunlight.

Needs of Watering and Nutrients:

During the bulb formation stage, the onion’s need for water and nutrients changes slightly changed. It requires 1 inch of water every 3 days. For nutrients, phosphorus and potassium are needed the most. Now you need to add potassium and phosphorus into your fertilizer.

Getting Mature:

Bulb maturity is the next stage of the onion plant life cycle. Over time, the bulb increases in size. The sign of mature in onion is big size of onion, you can also tell that bulb it getting mature when it plant start yellowing from the top and eventually fall over.

Watering:

When the onion bulb getting mature and approaching its harvest time, you need to reduce water on your plants. Because less water hardens the outer surface of the onion bulb, you can store it for longer after harvesting.

Disease and Pest:

Plants are always vulnerable to pests and diseases, even when they are close to harvesting. At this stage, pests like Seedcorn maggot, and Onion thrips, and diseases like downy mildew, Onion smut, Purple blotch, Slippery skin etc attack the onion plants. So you need to regularly check you plants and use proper pest control if you need.

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Harvesting:

Harvesting is the Next stage of onion growth. You can start harvesting when the onion plant is ready, and it is ready when the top of the plant is turning down or fully fallen over.

Harvesting Techniques:

For harvesting, you just need a garden fork. Now start digging up the onion, but try not to damage it. You also don’t need to cut off the bulb form the plant or leaves because it keep the onion form drying out.

Storing:

After a couple of days of harvesting, you can now cut the onion from its leaves. Now remove the outer layer when it is usually damaged, and put it into a dry and well-ventilated area for a couple of weeks. It is important because it helps the outer layer to get dry and tight up, and then can start using it and store it for future uses.

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Flowering:

The next onion plant growth stages is flowering. If you notice during or before the harvesting, some onions may start bolting. If some of you don’t know bolting, then it is a normal process that happens when the onion suddenly feels cold, warm or faces drought. In bolting, it starts to grow flower stems, which take up all resources to produce flowers and then seeds.

If you don’t want seeds from your onion, you can cut the bolt because it stops further onion bulb production. But if you do, then leave some onion plants with bolts for pollination.

Here is a video explaining what is bolting:

If you have bolting stems in all of your onions, try to remove them as soon as you see them because they turn the focus of its resources from bulb production to flowering and seed production and can also take up all the stored resources.

Seed Collection:

After the flower gets pollinated, it takes a few weeks to produce seeds. During those times, the flower stem continuously grows. But after some time, that flower produces seeds and turns so heavy that they fall down. So now you have to get those seeds from that stem and save it for next year.

Conclusion:

Understanding the onion growth stages is important for future onion farming. It has simple growth stages just like other Amaryllidaceae. After knowing each stage’s proper requirements, you will have strong and healthy onion yields.

I hop you understand the topic but if you still feel confusion in any of the above headings then feel free to ask it in the comment section and I will get back to you as soon as possible.