How to Grow an Onion from an Onion?

Onions are one of the most versatile and flavorful vegetables for home gardeners. But did you know that you can grow an onion from an onion? It may sound strange, but many people are doing it and so can you! Growing an onion from an onion is surprisingly easy—all you need is a pot, some soil, and of course, an onion!

This tutorial will explore the basics of successfully growing an onion from an onion. We'll look at what kind of soil and container are best to use and how to care for your new plants once they're sprouted! So if you're ready to try growing onions from onions, let's dive in!

Supplies Needed

To grow an onion from an onion, you will need the following supplies −

  • 1 onion

  • 1 pot or container that is at least 6 inches’ deep

  • Potting soil

  • Water

Step 1: Prepare the Seed

Peel the outer layers of the onion bulb until you reach the firm, white layers. Cut the onion in half crosswise so you can see the sprout in the center. Carefully remove one-half of the onion, keeping the sprout intact.

Place the half onion with the sprout facing up in a container filled with water for 3-4 days until you see white roots growing from the bottom.

Step 2: Plant the Seed

Next, you must fill your pot or container with potting soil. Once the pot is filled, take one of the onion halves and bury it in the soil so that the root end points downwards and the top end points upwards. Ensure that there are at least 2 inches of soil covering the onion.

After you have buried one of the onions, water the soil till it attains the required moisture without being soggy. Do repeat this process with the other half of the onion.

Step 3: Create the Right Environment

Once you have planted both halves of the onion, place the pot or container in an area that receives plenty of sunlight. Onions need at least 6 hours of sunlight per day in order to grow properly. Water your onions regularly, making sure to keep the soil moist but not soggy.

Step 4: Wait till Harvesting

In about 2-3 weeks, you should start to see green leaves poking through the soil. These leaves are called "scapes". Once the scapes appear, stop watering your onions as much and allow the soil to dry out somewhat between waterings. Continue to fertilize your onions every few weeks using a standard vegetable.

Tips for Success

Here is a set of tips to help you succeed in growing onions −

  • Start with a small onion. A big onion will have too much of its mass taken up by the edible portion and won't have enough left over to sprout new growth.

  • Cut off the root end of the onion, making sure to leave at least an inch or two of the root attached.

  • Onions are root vegetables, meaning they grow best in soil that is loose and well-drained.

  • Go for a sunny spot in the garden.

  • Water your onion regularly. Keep the soil moist but not soggy. Too much water can actually rot the roots of your onion plant!

  • The growing process can take several weeks, so be patient!

  • Cut onions once they reach their full size.

  • Cut the stem about an inch above the bulb of your onion, being careful not to damage the roots.

How to Care for Onion Plants till Harvesting?

Fertilize the plants with a balanced fertilizer, such as a 10-10-10 fertilizer, every 4-6 weeks. If your area is prone to heavy rainfall, use a fertilizer with higher nitrogen content. This will help the plants to grow more leaves and produce more onions. On the other hand, if you live in an area with very little rainfall, you will need to use a fertilizer that has a higher phosphorus content. This will help the plants to form strong roots so they can withstand the dry conditions.

Keep the area around the onions free of weeds, which can compete with the onions for water and nutrients. An effective way to keep onion plants free from the weed is to use a hoe or other hand tool to remove them regularly. Additionally, using a layer of mulch around the base of the onion plant can help prevent weed growth.

Once the onion leaves begin to yellow and fall over, stop watering the plants and allow the bulbs to dry out for 2-3 weeks before harvesting.

When to Harvest Your Onion?

How to know if onions are ready to harvest? Well, if the tops have fallen over and the bulb is about 1/3 its full size, they're good to go. You can tell if an onion is ready to harvest if the skin is dry and papery.

To harvest your onion, loosen the soil around the bulb with a garden fork and gently lift it from the ground. Cut off the top of the onion, about an inch above the bulb, and then brush away any dirt that is clinging to it. Store your onions in a cool, dry place out of direct sunlight.


Growing an onion from another onion is a fun and easy way to start your own vegetable garden. It requires minimal effort, but it can have huge rewards! You'll have fresh onions right in your backyard.

With the right strategy and guidance, you can even grow enough onions for multiple harvests throughout the year. So why not try it out? All you need is one onion and plenty of patience to start enjoying home-grown onions!

Updated on: 02-Mar-2023


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