The reason your onions may not be growing properly is because you might not be giving them the right nutrients, or perhaps your onions aren’t bulbing up due to the variety you’re choosing or the time of year you’re planting them. There are many reasons why your onion harvest may not grow well, bulb up, or be ready for harvest when you expect them to be. In this post, I’m going to share some things I’ve learned about growing onions so you can avoid my mistakes and have a successful harvest.
Choosing the Right Planting Method
I started most of my onions from starts, which are just small baby plants. I also started a few from seed but they remained pretty small. There’s definitely more to learn when it comes to starting onions from seed! However, the onions that I started from starts that I purchased have done much better.
One indication of whether you’re going to have a larger bulb is how quickly you can grow your plants. If you’re starting from seed, focus on getting those plants big, bushy, and healthy before they are halfway through their growing season. That’s one of the reasons why starting from starts or sets is advantageous. To learn more about planting onions from seeds, starts or sets, check out my previous post.
Selecting the Right Onion Variety
The variety you’re growing plays a significant role in your onion success. I have three varieties in my garden:
- Red Creole
- Texas Early White
- Texas Super Sweet
The variety is important because there are three types of onions. It all has to do with the amount of daylight hours during the summer solstice, the longest day of the year.
- Southern U.S.: Grow short-day onions because even the longest days here are shorter than those up north.
- Central U.S.: Grow intermediate-day onions.
- Northern U.S. and Alaska: Grow long-day onions because they have significant daylight during the summer solstice.
Onions are daylight-driven, and the plant starts forming a bulb once it reaches a specific amount of daylight hours. For example, if you plant onions in late fall and head toward winter, they won’t bulb up because daylight hours are decreasing. Here in Florida, planting them around winter and allowing daylight hours to gradually increase tells the plant to start forming a bulb.
Providing Adequate Nutrition
Another reason why your onions may not be growing or bulbing up is due to soil nutrition. Before planting my onion starts, I added chicken manure, blood meal, bone meal, and kelp meal as soil amendments. While this helped initially, I didn’t side-dress or add more fertilizer halfway through the season, particularly chicken manure. As a result, I ended up with some tiny onions.
The smaller onions also resulted from planting them too close together. While they had enough room to bulb out, they didn’t have enough room to share the nutrients. If you plant your onions closely together, you need to provide more fertilizer. Next season, I’ll be planting them further apart, about 4 to 6 inches, which seems to be the perfect distance.
Watering Your Onions Consistently
Watering is another critical factor for successful onion growth. If you don’t water your onions regularly, you’ll have problems. Too much water can cause rot and fungal issues, while too little water means the green growth won’t be large and bushy enough to support bulb growth.
During the winter, I water twice a week. This past winter was rainy, so I skipped watering whenever it rained. As spring arrived, I increased watering to three times a week and spot-watered plants where the soil dried up.
Knowing When to Harvest Onions
The best indicator of when to harvest an onion is when the tops fall over and fold, cutting off nutrition to the bulb. At this point, the bulb only receives nutrients from what’s left in the soil.
If left in the ground much longer, onions may start to rot and won’t store well. Onions are ready to harvest when the tops folded over easily, revealing some beautiful bulbs.
Curing and Storing Onion Harvest
After the onion harvest, I quickly sorted them into two groups:
- Ones to Cure: Larger, well-formed onions that will store well.
- Ones to Process: Smaller onions that didn’t complete bulbing properly.
For the ones to cure, I hung them up in bunches of similar varieties (red, white, and yellow) because each has a different shelf life.
To hang them, I tied a nylon string in a knot and looped it around the neck of each onion. I then pinched the string between my fingers, pulled it down, and tightened it.
The onions are hanging outside under my patio, with fans providing good airflow. They’ll remain hanging until the greens turn brown, which should take about two weeks. Once cured, I’ll braid them and place them in my pantry.
I hope you learned some valuable tips and had fun harvesting onions with me. Let’s make sure your next onion crop is bountiful and healthy. Happy gardening!
