Red onions are a crisp and flavorful addition to any dish, and because of their comparable flavor, they make great substitutions for other onions. Although onions are inexpensive to pick up from the grocery store, nothing beats growing your onions at home. Because of the ease that onions grow, there is nothing to lose by learning how to grow red onions.
The Allium family is home to many exciting and tasty plants that work well in various dishes. Aside from common yellow onions, well-known plants in the onion family include leeks, chives, shallots, scallions, and green onions. Are shallots red onions? While they are related, they are not quite the same.
Sweet onions are usually the go-to when grabbing produce, but red onions are an excellent addition to any dish with their sweet or spicy taste, depending on which variety you choose.
- Growing Red Onions
- Picking Onions to Grow
- Caring for Red Onions
Growing Red Onions
Growing onions is fun because of the different ways you can start them. If you’re running out of garden space or live in an area where the temperature is too cold for onions, there are easy workarounds for these hurdles. Keep reading to learn the difference between yellow and red onions and the purpose of red onions.
Although growing red onions from seed is an excellent choice, onions are versatile plants that grow in containers and even from scraps of other onions. Continue reading to discover different ways to grow onions and answer common questions like “How long does it take red onions to grow?”
Picking Onions to Grow
The planting times for onion seeds vary based on your location and your hardiness zone. Reference the USDA map to determine the average temperature and the best time to plant onion seeds. Selecting an onion variety also depends on the day length to determine how much sunlight your onions get.
Short-day onions thrive in southern parts of the United States where the weather is warmer. In these areas, sunlight typically lasts for at least ten hours of the day in the summer.
Intermediate onion varieties require slightly more sunlight to form bulbs. These onions grow well in the middle part of the country, with around 12 hours of sun a day.
Long-day onions grow best in the northernmost part of the country, receiving 14 hours of daylight. Onions are usually planted in spring or earlier with overwintering varieties in these zones.
Preparing to Plant Red Onions
Like most plants, onions thrive in specific soil conditions and a climate that allows them to germinate and grow. Whether you plan on growing onions in your garden bed or a pot indoors, select a location for your red onions to grow in full sun.
Red onions grow in soil with a neutral pH and in any soil type except clay. If your soil cannot grow red onions, consider growing onions in containers instead. Add fertilizer to your soil to improve the growing conditions and the growth of your onions.
Once the ground is workable, till the soil with a hoe to create a furrow in your garden – furrows are trenches between rows of your plants to help with irrigation. Mix in compost to add extra nutrients into the soil when you plant your seeds.
How to Start Growing Red Onions from Seed
Knowing how to plant red onion seeds includes proper spacing. Onion planting depth is important, too. Create holes about one to one and a half inches deep in your soil straight from one end of your garden bed to the other, leaving four inches between each hole. To plant multiple rows, leave ten inches between each row for room to walk and harvest.
Plant your seeds in the holes and cover the seeds with soil before watering thoroughly. As your onions grow green shoots, regularly water them with an inch of water.
How to Grow Red Onions in Containers Indoors
Plant onions eight weeks before the last frost for your area to get a jump start on the growing season area. Planting in containers offers more control over the growth of your plants, and if you leave your containers inside, you don’t have to worry about bad weather ruining your crops.
For the best way to grow red onions in pots, prepare your pot or container with potting soil and slow-release fertilizer. Prepping your soil allows your onion roots to get proper nutrition as germination occurs.
Monitor your soil temperature with a thermometer, and plant your seeds once the soil reaches 60°F. Plant several seeds inside the pot, evenly spaced, and water thoroughly. As green tops appear, thin them out until one strong sprout remains.
Growing Red Onions from Onions
You may be curious about how to grow onions from other onions – it is relatively straightforward. Using an onion, water, and some everyday items around your house, you can regrow an onion using scraps.
Use your onion as desired, leaving the root end aside to dry for 24 hours, then place the root end in the jar of water. Use toothpicks if needed to position the root end, so only the roots are in the water.
Leave the jar in direct sunlight and add new water as the water level falls. After several days, new roots should form. As your fresh onion grows, prepare your garden for the transplant.
Transplanting Red Onions
There is a little difference in the right months to plant onions in zone 7 and zone 5 or 9, so pay attention to the weather. Once the ground is workable following the last frost in your area, start transplanting your onions outside. When digging holes for your onions, dig holes two to three inches deep and one to two inches apart. How far to plant onions apart is important so the plants have room to grow. Leave at least ten inches between rows.
Add organic matter mulch around your plants to help your soil retain moisture and keep weeds from sprouting. Because onion roots are shallow, weeding by hand causes damage or stress to your plants.
Growing Onions from Onion Sets
A quick alternative to growing red onions from seeds is planting out onion sets, bundles of onions explicitly packaged to be regrown.
If you grow your sets in a container, use potting mix and plant your sets three inches apart. Water your sets weekly, allowing the soil to dry between each watering. Depending on the type of onions planted, your sets should mature in about three months.
How do Red Onions Grow from Bulbs?
Red onion bulbs are the underground stems of onions surrounded by flesh and papery skin. Within the bulb, the onion stores food to grow green onion tops.
Because these bulbs contain everything required to grow onions, you have all you need to kickstart your onion garden if you purchase a pack of bulbs. Since you don’t need to worry about germination, there is more flexibility when planting bulbs as long as your soil has the nutrients to support bulb growth.
One option for growing from bulbs is to plant them in raised beds, which allows you to keep your garden outdoors while avoiding common issues like weeds and pests such as nematodes and onion maggots.
Caring for Red Onions
For the first month after planting onions, water them, avoiding the green parts of your onion seedlings and focusing on the soil around the plant. Watering this way helps avoid fungal diseases. After the first month, your onions do not require as much water, and if you live in a rainy area, you may be able to let nature do the watering for you.
After your onions grow, they develop flower stalks. These stalks fall over and dry up, signaling that it’s time to harvest your onions. If you planted in early spring, this occurs around late summer.
Cut the green tops off your onion bulb and dig the area around the soil to pull the bulb out. Set them on a paper towel or newspaper to allow the skin to dry. Store your onions in a cool, dry place.
Dealing with Pests
Row covers protect your crops from insect pests, and crop rotation effectively keeps bugs in the soil away from your crops. If you need to treat your plants, insecticidal soap is easy to make at home.
Pour water, rubbing alcohol, and liquid dish soap into a spray bottle to create this spray. Spritz onto the leaves of your plants to kill insects like thrips and onion flies.
Companion planting is a natural way to prevent pest problems. Tomatoes and carrots are great to plant near onions but bad companion plants for onions include asparagus and beans.
Whether you prefer green, yellow, or red–onions are easy biennials, and it’s a task everyone should try. Since they’re so simple they are to grow, we’re sure it’s a gardening hobby you’ll want to do year after year. After you master one method of growing red onions, tackle another until you harvest as many as you can handle.
If our info helped you learn how to grow red onions, please share our tips on growing red onions from seed on Facebook and Pinterest with your fellow gardeners.