A steaming bowl of chili or homemade soup is just not the same without adding an allium such as shallots, green onions (scallions), garlic, leeks, or your favorite onion varieties. And, their flavor is even better when you grow your own at home. We show you how to plant onions from seeds, sets, or the leftover scraps from the grocery store in a few easy steps.
Onions are not only delicious as a hamburger topping or hot dog relish, but they are also packed full of antioxidants. They have anti-inflammatory properties, reduce cholesterol and decrease triglycerides.
There are also many types of onions to suit your taste, from yellow and sweet onions to red and white onions. No matter which onion type is your favorite, they are all easy to grow in the garden, and there is more than one way to grow onions.
Ways to Plant and Care for Onions
Purchase onion seeds and sets from garden centers or regrow onions from scraps and enjoy an onion crop of your own at the end of the growing season. Why run to the grocery store every time a recipe calls for an onion when growing onions is so simple?
Learn how to plant onions from seeds, onion sets, or scraps and provide them the care they need. We also explain when to harvest your onions and ways to store them.
Preparing for Planting Onions
Before planting onions, it’s a great idea to understand what onions require to grow healthy and how to care for them to help them thrive. It’s also essential to choose the right onion type for your climate to ensure a good crop.
The first step to grow onions is to choose the proper onions for your location. Long-day onions require 14 to 16 hours of sunlight each day, so if you live in an area where you get less light, the onions don’t form bulbs.
On the other hand, short-day onions only need about ten hours of daily sunshine and grow well in a mild winter region, while day-neutral onions produce well in any area, regardless of day length.
The next step in garden preparation is to choose the location in your yard for planting. This is essential whether you are preparing a garden bed or planting the onions in a raised bed.
Watch how the sun travels through your yard from morning until evening, and pick a spot where the garden receives the most light.
Finally, test the soil with a kit to ensure it’s between 6 and 6.8 pH. To make the dirt more acidic, add iron sulfate, aluminum sulfate, or powdered sulfur and add lime to increase the alkalinity.
How to Plant Onions from Seeds
If you opt to plant shallot seeds or another variety of onion, the best time to plant onions is to start them indoors in early spring before the last frost to give them a chance to grow and strengthen before you plant them outdoors. Here is how to plant onions from seeds.
When you plant red onions or white varieties, start your seeds at least six weeks before the last frost. Fill a seed starting tray with soil and place four seeds a half-inch deep into the dirt of each cell. Spray the tray with water to moisten the soil without saturating it and set it on a sunny windowsill.
Keep the dirt damp as the seedlings grow, and trim the onion tops back to three inches if they grow too long to prevent drooping.
Transplanting Onion Seedlings in the Garden
After the onion seeds germinate and the outside temperatures are about 50°F, it’s time to move them outdoors into the garden. If you don’t have a garden bed, consider planting onions in raised beds.
The best way to plant onions after growing them from seeds is to harden them off first. Take the plants outside each day for a couple of hours to help them acclimate to different weather conditions. After a week, they are ready for transplanting.
Start by fertilizing the soil with nitrogen to help the onions grow. Nitrogen is available as a fertilizer or in composted manure and bone meal.
Dig a hole for each plant that is roughly half an inch deep. Spacing when planting onions and other crops is important, so make sure to place each hole four inches apart with each furrow, or row, twelve inches apart to prevent bunching and crowding.
Set each plant into a hole and cover the base with dirt. Onions require a lot of water, so make sure they receive an inch each week.
How to Plant Onions from Onions
Believe it or not, but some vegetables, such as celery, potatoes, carrots, and onions, regrow from the parts you toss in the trash. Here is how to plant an onion from the scraps of an old onion.
Planting onions from onions is easy, as long as you have an onion to start with. To grow onions from onions, slice the onion an inch from the bottom and set it aside to dry for a day or two.
After the onion is dry to the touch, fill a glass with water. Poke a toothpick into each side of the onion and position it on the water glass rim so that the onion bottom soaks in the water.
After about four days, roots begin emerging from the onion, and it’s time to plant the onion in a pot of dirt or in the outside garden.
Growing Onions from Onion Sets
If you do not have the patience to wait for the germination of onion seeds, consider planting onions from sets, or plant green onion bulbs. These are small onions about the size of a nickel, allowing you to plant them straight in the garden.
When planting onions from bulbs, prepare the garden and dig holes four to five inches apart and space rows 12 to 18 inches apart. Make the holes one inch deep, set an onion bulb into each spot, and cover them with dirt.
When growing onions from sets, water the garden thoroughly after planting and spread mulch around each plant to stop weed growth.
Caring for Garden Onions
Knowing how to plant onions from seeds or onions is only the first step. Once you have the plants in the garden soil, it’s important to give them the right amount of sunshine, water, and fertilizer to help them flourish.
Make sure to plant your garden in a full sun location of your yard. Fertilize your onion plants with nitrogen once every few weeks to get healthy, big onion bulbs.
Mulch the bed with straw or another natural material, and give the plants an inch of water each week. Reduce watering once they reach their full size, and the green tops stop growing.
Keep an eye on your plants for pests such as thrips and onion maggots. Thrips are tiny, tan insects that are as fat as a sewing needle and a common problem for onions.
If you spot them on your plants, use insecticidal soap to eliminate them. Onion maggots are also a nuisance that lay eggs on the plant’s base, and covering them with fine mesh netting helps alleviate the problem.
When and How to Harvest Onions
After you learn how to plant a sprouted onion and you go through the necessary steps to ensure the plant grows healthy, you’re probably wondering how long you have to wait before you get to harvest onions.
How long do shallots take to grow, as well as other onion species? Onions are a cool weather crop and take about three months to grow. Mature onions have yellow foliage that falls over in late summer. Bend the stalks over to speed up the ripening process and loosen the soil around the base to help the onions dry.
Once the tops are brown, pull the onion bulbs out of the ground carefully to avoid bruising them. Plants with flower stalks are not useful for storing but are okay for eating within a few days.
Ways to Cure and Store Onions
Planting sprouted onions is both fun and rewarding, especially when you harvest a good onion crop. But, what is the best way to keep onions, and how long do they last before spoiling?
After pulling the onions from the ground, cut the tops back an inch or two, clip the roots, and let them sit out in a dry part of the garden for a few days to cure.
The best way to keep onions fresh is to hang the onions in mesh bags or a nylon stocking in a cool, dark area such as a root cellar or basement. Check them periodically and remove those that begin sprouting or rotting.
Do not store them in the refrigerator and keep them away from potatoes. What is the onion shelf life in a dark place? Onions last a few months stored in this manner.
The aroma and taste of onions is something that can’t be beat, whether you prefer yours sauteed in butter or raw and crispy, and the health benefits of eating these alliums is a bonus.
Fortunately, growing your own onions is a fairly simple task and saves you trips to the grocery store.
Knowing how to plant onions keeps your kitchen well-stocked and your savory recipes flavorful, so why not share our onion growing guide and tips with the gardeners in your life on Facebook and Pinterest?