Eighty-seven percent of the onion varieties used in cooking is culled from the common yellow onion. While there are many varieties of yellow onion, its less utilized cousin, the red onion, has its place in the kitchen for its mild sweet flavor and brilliant color. So, are red onions easy to grow? When is planting and harvesting time for red onions? Read on to learn more.
Growing red onions is as easy as any other type of onion. All onions are biennials, meaning they take two years to complete their life cycle. In the first year, seed grows, forming modified leaves and tiny underground bulbs.
In the succeeding year, red onion bulbs mature until they’re ready to harvest. Most gardeners plant onion sets, the second year small red onion bulbs, to hasten the maturation and harvest of the onions.
With regards to white vs. red onions, there’s no difference when growing red onions as opposed to growing onions in general. There is a difference in flavor with white onions milder than red, and having a shorter storage life than red onions. Both types of onion come in a multitude of varieties with varying planting times, thus different harvesting times.
To get onions off to a good start, mix an organic or time release fertilizer into the soil prior to planting. Make sure the fertilizer is beneath the planting furrow. This is called “banding” and makes sure the nutrients are exactly where the young onion roots can find them. Mix a 2-inch (5 cm.) layer of compost into the soil before adding the fertilizer.
All onions need plenty of sun and well-draining soil with a pH between 6.0 and 6.8. Set the onion bulbs 1-2 inches (2.5-5 cm.) deep so the roots are well covered but the neck isn’t set too deeply. Space the plants 6 inches (15 cm.) apart in furrows 12 inches (30 cm.) apart. Water the onions until they are wet, but not drenched.
Onion roots are shallow, so they need a consistent supply of water, which will also garner you sweeter onions. You can lay a light layer of grass clippings or other fine mulch around the onions, but be sure to keep it away from the onion tops which need full access to the sun.
Okay, so you have patiently waited throughout the summer and are itching to dig up the red onions and try them. The question is, when is the right time to harvest red onions? You can pull onions after a few weeks if you just want to use them as scallions, but for full size onions, you must be patient and let them mature.
Onions are ready to harvest when the bulbs are large and the green tops begin to yellow and fall over. Stop watering the onion when around 10 percent of the tops begin to fall over. You can now harvest the onions or leave them in the ground to be stored and used as needed.
To harvest the onions, dig the onions up and shake off the loose soil. Lay them out to cure with the tops still attached, in a warm, airy place. Keep the onions dry with good air circulation so they don’t rot. As the onions cure, the roots shrivel and the necks dry out. Allow the onions to cure for seven to 10 days and then either braid the tops for storage or remove the tops and roots with pruning shears. Store the cured onions in a cool, dry place between 35-50 F. (1-10 C.).
Bulbing onions probably originated in the region of the world now known as Pakistan. The Egyptians were said to have built the pyramids on a diet that included a generous supply of onions. Imagine straining to move stones that weighed tons when you and all of your co-workers had a steady diet of onions - not a pretty picture. Regardless, onions have been an important food item in Egypt since 3200 BC.
Onions came to the New World with the Spaniards and shortly thereafter we discovered how great they were in sour cream and on a hamburger. The rest is history.
Harvesting your onions can be done throughout the growing season. Onion tops can be cut and used like green onions for a salad or soup. You can also pull a onion right out of the ground and eat it even if it’s not completely full grown. To tell when your onions are mature the foliage will topple over and start to turn yellow. This is when you remove the dirt around the base of the onion and let it begin to dry out. A week later on a dry day dig up your onions and place them in the sun. Drying for storage can take any where from 7-14 days. Or you can just eat them fresh.
After your onions are completely dry place them in a stocking. Yes, you read this right! Nylon stockings are perfect because they allow the onions to breath. Place one onion in the bottom and tie a knot, continue tying knots after each one and eventually you will end up with a string of onion pearls. Store the onions hanging in a dry cool area and they should last up to 9 months.
Onions seeded in October/December or transplanted in January/February should produce bulbs in May/July.
If used as green onions, they may be picked from the time they are pencil size until they begin to form bulbs.
For dry-bulb onions, let the plants grow larger. The onions are ready when the main stem begins to get weak and fall (Fig. 3). Pull the plants out of the soil.
Leave them lying in the garden for 1 to 2 days to dry. Then remove the tops and roots and let them keep drying in baskets or boxes.
While most of the onions used for cooking are yellow onions, the mild, sweet taste and attractive coloring of red onions make them a favorite for salads and colorful garnishing for many recipes. If you’d like to grow your own red onions, it’s easy, fun and economical, since red onions last for months in storage.
Planting red onions uses the same method as yellow onions. They’re biennials, which means they take two years to mature if planted from seeds. The easiest way to plant red onions is to use onion sets. These sets are second year bulbs that you can find at a garden store. Planting red onion sets will give you mature, red onions within three to four months from planting.
Before planting your red onions, find a sunny location for your garden and test the soil for pH levels and nutrients. Once you know if your soil needs any adjustments, you can add nutrient-rich organic fertilizer to the garden soil to boost your onion bulb growth. Follow these steps for planting red onions:
Just like other onion varieties, red onions are ready to harvest when the bulbs grow large enough for you to see the onion tops pushing up from the soil. You’ll also notice that the onion stalks are turning yellow and tipping over. When this happens, your onions are ready to cure and harvest.
Curing your red onions is a simple process. All you have to do is pull the bulbs out of the soil and allow them to dry for about two weeks. You can either leave them in your garden to dry, or gather the bulbs and place them in a dry, well-ventilated area. No matter which drying method you choose, make sure the bulbs have plenty of air circulation, so they don’t grow mold or fungus, which leads to rotting.
Once you cure your red onion bulbs, cut the dried onion stalks about 1 inch from the top of the bulb. Place the bulbs in containers that allow exposure to the air, such as mesh bags, slatted wooden tubs or paper bags with punched holes that allow air circulation. Place the storage containers in a cool, dry place between 32° (0°C) to 50°F (10°C).