Step by Step Guide on How to Grow Onions:
1. Select which onion variety you would like to grow.
Onions come in many varieties:
White onions are a classic, all-purpose onion with a mild flavor and crisp texture. They are great for salads, sandwiches, and soups!
Red onions are a bit sweeter and have a mild flavor, making them perfect for salads and sandwiches.
Yellow onions are also mild but with a slightly stronger flavor, great for sautéing and roasting.
Sweet onions are the sweetest of all the onions, with a mild flavor, and are perfect for adding a touch of sweetness to dishes!
So...pick whichever sounds the tastiest to you!
2. Choose the perfect spot to plant your onions.
Onions need lots of sun and thrive in well-draining soil. The spot you choose should ideally get at least 6-8 hours of direct sunlight each day.
3. Sow your seeds.
Plant the seeds roughly 1-2 inches deep and about 4 inches apart.
4. Keep your onions hydrated.
Make sure to keep the soil consistently moist by watering regularly.
5. Fertilize your onions.
When your onion plants reach around 4 inches in height, it's time to give them a nitrogen-rich fertilizer.
6. Thin your onions.
Also around the 4 inch mark...you'll want to also thin them out so that they are spaced (at least 4-6 inches apart) to give the remaining plants enough room to grow.
7. Time to harvest!
When the leaves begin to turn yellow, your onions are ready to be harvested. Using a shovel, carefully dig up the onions, being careful not to damage the bulbs.
8. Cure your onions.
Lay your onions in a single layer out in the sun to cure. This will help to toughen the skins and improve their flavor.
9. Store your onions.
Once the onions are cured, you'll want to store them in a cool, dark place for several months.
Recommended Materials to Grow Onions
- Onion Seeds or Onion Sets: Yellow Sweet Spanish Onion Seeds
- Nitrogen-Rich Fertilizer: Jobe’s Organics All-Purpose Fertilizer
- Gardening Shovel: Fiskars 48 Inch Steel Garden Shovel
- Potting Soil: Miracle-Gro Potting Soil
- Sunlight Monitor: Light Meter with Lux/Foot Candle Measurement
How Long Does it Take to Grow an Onion?
Onions are surprisingly fast growers! From planting to harvest, expect your onions to be ready in as little as two months! Once planted, onions will germinate in roughly 7-10 days. From there, they will reach a harvestable size in as little as 8-10 weeks.
How Do You Grow Onions from an Onion?
It's so easy to regrow onions from scraps! All you need is an onion, some water, and a sunny spot. Just cut off the top of the onion and leave a few inches of the onion attached to the roots. Next...place the onion in a shallow bowl filled with about an inch of water and set it in a sunny spot. Every few days, change the water and watch with excitement as the onion begins to regrow! Once the onion has grown a couple of inches, you can transfer it to soil and follow the above step by step guide and watch it grow even more! Give it a try!
Can You Grow Onions from Store-Bought?
Yes! You can absolutely grow onions from store-bought! Just follow the above instructions on How Do You Grow Onions from an Onion.
What Happens if You Plant a Whole Onion?
Planting a whole onion is actually a great way to get your onions started! The onion will break down in the soil and provide nutrients to the surrounding plants. However, it is important to note that onions planted this way will take much longer to mature. It can take up to 3 months for a whole onion to fully mature and be ready to be harvested. For quicker results, it is best to plant onion seeds or onion sets (small onions with roots already established).
How Many Onions Can You Grow from One Onion?
This largely depends on the variety of onion you are growing. Onions can be divided into two main categories: "short-day" onions and "long-day" onions. Short-day onions will produce only a few bulbs from one onion, while long-day onions can produce up to 8 or more bulbs from one onion!
Examples of short-day onions include:
- Vidalia
- Texas Grano
- Granex varieties.
Examples of long-day onions include:
- Walla Walla
- Yellow Sweet Spanish
- Red Torpedo varieties
Depending on your variety, you can expect to get anywhere from a few bulbs to a whole bunch of onions from just one onion!
What is the Best Month to Plant Onions?
When it comes to planting onions, timing is everything! Onions are cool-season crops, so they prefer cooler temperatures.
In warmer climates: the best time to plant onions is in the fall for a winter harvest.
In cooler climates: the best time to plant onions is in early spring for a summer harvest.
If you want an early spring harvest: you can also plant onions in the late winter.
No matter when you plant your onions, you can expect them to be ready for harvest in 2-3 months.
How Many Times Can You Regrow an Onion?
You can expect to be able to regrow your onions at least two or three times.
How Do You Know when to Pull Onions?
When it comes to harvesting onions, timing is everything! Onions are ready to be harvested when the leaves begin to turn yellow and the tops start to fall over. You can also tell when onions are ready to be harvested by gently tugging on the onion – if it comes up easily, it’s ready to be pulled.
Once you’ve harvested your onions, be sure to store them in a cool, dark place for maximum shelf life.
Can You Grow Onions Indoors?
Yes – you can absolutely grow onions indoors! A sunny spot and some soil is all you need to get started. Cut the top off of the onion, (leaving a few inches of the onion attached to the roots). Place into a shallow bowl filled with approx. 1 inch of water then set it in a sunny spot. Every few days change the water. Once the onion has grown several inches, you can transfer it to soil!
What Happens When You Plant an Onion That Has Sprouted?
Planting an onion that has sprouted can be a great way to get your onions started! The onion will break down in the soil and provide nutrients to the surrounding plants. However, it is important to note that onions planted this way will take much longer to mature. It can take up to 3 months for a sprouted onion to fully mature and be ready to be harvested.
For quicker results, it is best to plant onion seeds or onion sets (small onions with roots already established). But if you’re feeling adventurous, give it a try and see what happens! You may be pleasantly surprised!
Will Onions Keep Growing if Left in Ground?
Yes – onions will continue to grow if left in the ground! However, it is important to note that onions will not grow to their full potential if left in the ground for too long. Onions need to be harvested before they become overripe in order to ensure maximum flavor and freshness. If left too long, onions can also become woody and tough. So be sure to check your onions regularly and harvest them when they reach the desired size.
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