How to Plant a Sprouted Onion

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So, you have an onion or two that you bought from the grocery store, that have now sprouted in the pantry. And you’re wondering, “Can I plant these sprouted onions and grow a new, fresh onion?”

In short the answer is, YES! You can plant a sprouted onion and grow a new one. Actually usually you’ll get three new onions from one sprouted onion!

But, you can’t just plant the sprouted onion in the ground. You’ll need to do a little bit of prep work first. Don’t worry, it’s not hard at all.

Step 1

First, you need to peel the onion, layer by layer, down to the center.

Chances are some of the outer layers will be soft and maybe starting to rot if your onion has started sprouting. If not though, you can still use these outer layers of onion.

You want to peel all the way down until you get to just the clump of green sprouts.

I don’t use a special tool for this. I just peel the layers off with my hands.

Step 2

Once you get to the center of your onion, then you want to carefully peel away the additional layers until you start to revel separate plants!

Usually each sprouted onion will contain three separate plants.

Step 3

Separate each onion plant by carefully cutting apart at the root with a serrated kitchen knife.

Step 4

Now it’s time to plant your onion sprouts.

Your onion sprouts will hang around for up to 3 weeks before you need to plant them. You do not need to store them in water or soak them before planting. Do store them in a cool dry place though.

Onion plants don’t need to be buried very deep. You should plant the seedlings just 1″ into the ground and space them at least 4″ apart so the bulbs have room to grow.

Planted onion sprouts will take about 3 weeks to look perky. Keep them watered and plant them in a place that gets plenty of sun.

Step 5

Continue to water and weed around your onion plants. Fertilize if your soil is not very rich.

Onions grow best in fertilized, well-drained, somewhat acidic soil and they like full sun. You can use organic (manure, compost, etc.) or store-bought fertilizer to ensure your soil has the nutrients it needs to nourish your onion to its fullest potential.

Your onions should grow for about 3 months to reach optimum size which is when the bulb reaches the size of a baseball. You will be able to see the top of the onion as it grows and can get a good idea of its size without digging it up.

You do not want your onion plant to flower. If it does, then you’ll want to harvest that plant.

Step 6

Harvest your onions.

If your onion does not flower then you can let it grow up until the first frost. Harvest by pulling the onion out of the ground and then brushing them to remove dirt.

Do not wash onions. You want to keep the onions dry to avoid rot. Store them in a cool dry place. Onions can usually be stored for up to 6 weeks or more.

If your onion begins to sprout before you get to use them… you now know what to do! Use that sprouted onion to grow more onions!

Did you know you can also plant a sprouted potato?

Learn how to plant a potato that has sprouted!

Now let’s make some yummy food!

While you’re here, check out my easy recipes to get ideas for what to make with your garden fresh onions!

Browse all my recipes