How to Grow Onions

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Whether you’re a beginning gardener or a pro, growing onions can be a rewarding and simple process. Let’s walk through the secrets of how to grow onions at home in your garden.

Why Grow Onions?

Bulb onions are relatively easy to grow and store, making them an ideal crop for home gardeners. They are hardy and can adapt to various climates and soil types. Growing onions ensures you have a fresh, organic supply on hand, enhancing the taste of your meals and providing numerous health benefits, such as rich vitamins, minerals, and antioxidants.

Types of Onions

Before you start planting onion plants, it’s important to understand the different types of onions available. Onions can be categorized by their growing seasons and purposes:

1. Short-Day Onions: Ideal for southern regions with mild winters. These onions require 10-12 hours of daylight and are typically planted in the fall.
2. Long-Day Onions: Suitable for northern regions with longer daylight hours during the summer. They need 14-16 hours of daylight and are usually planted in early spring.
3. Intermediate-Day Onions: These onions can adapt to various regions, requiring 12-14 hours of daylight.
4. Day Neutral Onions: These onions are even more adaptable and are the best onions for growing in Oklahoma, zone 7.

Additionally, onions come in various colors and flavors, such as yellow, red, and white, each with its unique culinary uses. There are also bunching onions as well, but we are focusing on bulb onions in this post.

To begin growing onions, you’ll need to choose between starting from seeds, sets (small onion bulbs), or transplants. Each method has its advantages and may suit different gardeners’ needs and climates. We will cover the essential steps for each method, including soil preparation, planting, watering, and harvesting techniques.

If you want to read the full story of how we got started growing our own food at Little Sprouts and get all the basics to start yourself, check this out. The Journey of the Little Sprouts: A Guide for Growing a Better Tomorrow.

Planting Onions

Onions thrive in well-drained, loose soil with a pH between 6.0 and 7.0. They require full sun exposure and benefit from organic matter such as compost or well-rotted manure.

They enjoy sandy soil and won’t fare well in heavy clay soil. There’s not enough oxygen for the onion roots or drainage to keep them from rotting. Proper soil preparation ensures healthy root development and robust growth.

Depending on your chosen method (seeds, sets, or transplants), the planting process will vary slightly.

✔Here’s a link to a great vegetable garden planner you can print right out and use at home! So cute!

Depending on your climate, you can plant onions in late summer or late winter. The right time for your area is when it’s not too hot. They need fertile soil but also good drainage. You need to find out if your area works best for long-day varieties or short-day varieties because day length is the key to what type of onions to grow.

You’ll need to choose between red onions, yellow onions, or white onions. And the structure of your soil is key. If you have heavy clay soils, you will always get small bulbs instead of the nice large bulbs you long for because there is not enough air in the soil for them to bulb up to their full potential.

You can get the seeds online, but the local garden center is a good option as well. Onions can get fungal disease such as downy mildew, but other than that, they don’t get many plant diseases or pests. 

When to plant onions in Oklahoma

In Oklahoma, the timing for planting onions depends on the type of onion you are growing and the specific climate conditions in your area. Here’s a general guideline for planting onions in Oklahoma:

Short-day onions are ideal for southern regions, including Oklahoma. They require 10-12 hours of daylight and are best planted in the fall.

• Planting Time: Late October to early December
• Harvest Time: Spring to early summer (around May to June)

Long-day onions are not typically recommended for Oklahoma because they require 14-16 hours of daylight, which is more suited to northern regions.

Intermediate-day onions and day neutral onions can adapt well to the Oklahoma climate, needing 12-14 hours of daylight.

• Planting Time: Early to mid-February
• Harvest Time: Early Summer (around May)

Check out this month by month garden planting guide for all of your Oklahoma crop planting times.

General Tips for Planting Onions in Oklahoma

1. Soil Preparation: Onions prefer well-drained, loose soil with a pH between 6.0 and 7.0. Adding compost or well-rotted manure can improve soil fertility.
2. Planting Depth: Plant onion sets or fresh onion transplants about 1 inch deep or less. The closer to the top of the soil the better. You just need enough for them not to fall over. Plant them 4-6 inches apart in rows spaced 12-18 inches apart. Plant onion seeds a little earlier in pots and then transplant them, or in the ground around January (for zone 7).
3. Watering: Onions need consistent moisture, especially during the bulbing phase. Ensure the soil remains evenly moist but not waterlogged. Onions need about 1 inch of water per week.
4. Mulching: Applying mulch can help retain moisture, control weeds, and regulate soil temperature.
5. Fertilizing: Use a balanced fertilizer at planting time and again during the growing season to promote healthy growth.

By following these guidelines and adjusting based on local weather conditions, you can achieve a successful onion crop in Oklahoma.

Harvesting and Storing Onions

Knowing when and how to harvest your onions is key to ensuring their flavor and longevity. you need to know the signs of maturity, the harvesting process, and the best practices for curing and storing your onions to enjoy them year-round.

When you get good bulb formation, you can pull your onions at any time you need some for your recipes. If you want to get a large bulb, you can let them grow longer, but remember once it starts getting hot and the soil temperature reaches 80 degrees, the onions won’t continue to grow and they may rot.

Once the onions start sending up stalks with flowers on top, they are bolting or reproducing so you need to crack the tops over as close to the bottom as possible. If the tops fall over on their own, your onions are perfectly ready!

Make sure to plant your onions in a different area each year to cut down on pests and diseases. Crop rotation is important for every crop you grow in the garden. Also choosing to plant them with good companion plants is key. Onions are a great companion plant for many garden plants.

You can cut your onions and cure them in the sun for a few days and then store them in a mesh bag, or you can leave the tops on, cure them in the sun, and braid them up to hang. Putting them in nylon stockings with a knot in between each onion is a great way to store onions as well.

Troubleshooting Onion Problems

From pests to diseases, onions can face several challenges during their growth cycle. This section will provide solutions to common issues, helping you troubleshoot and maintain a healthy crop.

1. Pests: Onion maggots and thrips can be an issue. Use insecticidal soap or appropriate organic treatments to manage these pests.
2. Diseases: Ensure good air circulation around the plants and avoid overwatering to prevent fungal diseases.

Growing onions can be a fulfilling and productive addition to your gardening endeavors. With the right knowledge and care, you’ll enjoy a bountiful harvest of this indispensable kitchen staple. Follow this comprehensive guide to ensure your onion-growing journey is a success!

What to do with too many onions

If you find yourself with way too many onions, check out this great guide for what to do with excess onions from the garden.

Walking onions

Egyptian Walking Onions, also known as Tree Onions or Topset Onions, are a unique and hardy variety of perennial onions that are easy to grow and care for. They are named for their unusual way of propagating: instead of producing seeds, they develop small bulbils (miniature bulbs) at the top of their stems, which eventually fall over and take root, “walking” to a new location.

In addition to walking onions, there are also bunching onions, sometimes called green onions or scallions.

Are onions good for you?

onions are very good for you and offer numerous health benefits. Here are some of the key reasons why onions are a healthy addition to your diet:

1. Rich in Nutrients:
   • Onions are low in calories but high in vitamins and minerals. A medium-sized onion contains about 44 calories and provides significant amounts of vitamin C, vitamin B6, folate, and potassium.
2. Antioxidants:
   • Onions are packed with antioxidants, including quercetin and sulfur compounds. These antioxidants help neutralize harmful free radicals in the body, reducing oxidative stress and potentially lowering the risk of chronic diseases.

1. Heart Health:
   • The antioxidants in onions, particularly quercetin, have been shown to reduce blood pressure and lower cholesterol levels, promoting overall cardiovascular health.
   • Onions also contain sulfur compounds that can help prevent blood clot formation, reducing the risk of heart attacks and strokes.
2. Anti-Inflammatory Properties:
   • Onions have anti-inflammatory effects that can help reduce inflammation in the body. This can be beneficial for conditions such as arthritis and other inflammatory diseases.
3. Immune System Boost:
   • The high vitamin C content in onions boosts the immune system, helping the body fight off infections and illnesses.
4. Cancer Prevention:
   • Some studies suggest that the sulfur compounds and antioxidants in onions may help reduce the risk of certain types of cancer, including stomach, colon, and prostate cancer.
5. Digestive Health:
   • Onions are a good source of dietary fiber, which promotes healthy digestion and regular bowel movements. They also contain prebiotics, which feed the beneficial bacteria in your gut, supporting overall gut health.
6. Bone Health:
   • Onions contain compounds that may help increase bone density and reduce the risk of osteoporosis, particularly in postmenopausal women.

Other Benefits

1. Blood Sugar Regulation:
   • Onions may help regulate blood sugar levels, making them a good addition to the diet for people with diabetes or those at risk of developing the condition.
2. Antibacterial Properties:
   • Onions have natural antibacterial properties that can help fight off harmful bacteria, supporting overall health.