Can You Grow Another Onion From an Onion Bulb?
Planting bulbs is a popular way to start onions growing in your garden.
They are usually available before the final frost.
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Or you’ve got the option to plant in autumn about a month before the first frost.
Plant the bulbs when you get them.
If this isn’t possible, store them in a cool, dry location for up to two weeks.
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Once established, onions tolerate temperatures of 20 degrees Fahrenheit along with frost and light freezing.
Hard freezes damage young plants, so protect bulbs withnatural mulch, such as straw.
grass clippings, or pine needles.
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Another way to prevent frost damage is using row covers.
Before You Begin
Start by preparing your planting bed.
Size can vary so look for ones about 3/4 of an inch in diameter.
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Locate a retailer that lets you select instead of buying prepackaged bulbs.
it’s possible for you to discard soft, damaged, or big ones.
Large bulbs tend to flower or produce smaller onions.
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Bulbs that flower quickly rot and should be harvested and used immediately.
Opinions differ about removing green sprouts before planting.
Some gardeners say snipping them off results in better root growth.
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Others say sprouted bulbs give a head start on leafy growth.
Try both ways and see what works best in your patch.
Prepare the Planting Site
Choose a spot that receives sun all day.
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Work the aged compost into the soil or potting mix.
In the garden, use the hoe to dig a narrow trench about 1 inch deep.
Potted onions need 3 inches of space so choose a 12-inch pot to accommodate four bulbs.
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Space the rows at least 8 inches apart.
To harvest green onions, space bulbs 3 inches apart.
Make holes 1 inch deep and 3 inches apart if growing in containers.
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Pack the soil firmly around the bulb keeping the stem and top above soil level.
Thissetsthe bulb and keeps it in the correct position during planting.
Upside-down bulbs rarely sprout.
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Water Gently and Mulch
Drip irrigationis ideal for watering onions.
Otherwise, use a hose with aspray nozzleor a watering can with a rose spout.
Cover the planting bed or pot with a light natural mulch.
Green onions are ready in three to four weeks.
Mature onions grow above or partially above soil level so it’s possible for you to monitor the size.
Reduce or stop watering to allow their tops to dry and die back before harvest.
Fertilize every two weeks during its leafy growth with an NPK 10-10-10 or use organicbone mealandblood mealonce a month.
Fun Fact
Every leaf on an onion plant represents one ring of growth for the bulb.
Harvest and Cure
Harvest green onions when leaves are about 8 inches tall.
Full-size onions areready to harvestwhen the green tops and leaves fall over.
After leaves and stems dry, check the top around the stem.
Continue tocure the onionsfor a few days before storing them in a cool, dark location.
Plant as early as the soil can be worked in your growing zone.
Onions take 12 to 14 weeks to reach full size.
Bulbs planted later can be harvested as green onions.
This is your choice.
Soaking may result in quicker sprouting but dry sets can sprout as early as four days after planting.
Plant according to the size of the bulb, but generally the depth is about 1 inch.
Keeping the root side down and the top above the soil level is the most important.
How Do I Get My Onions to Grow Bigger?, University of New Hampshire Extension
