By Jennifer Poindexter
Onions are inexpensive to buy, but they taste much better when grown fresh in the garden. Plus, they’re a simple crop to grow. Are you toying with the idea of growing your own onions? If so, I have some information for you. I’m not going to tell you how to grow onions.
Instead, I’m going to help you overcome some common obstacles gardeners face when growing their own. If you’re interested in ensuring your onions do well in the garden, here are the common mistakes you should avoid making when growing onions:
1. Transplants vs. Sets: Deciding Which Is Best
Transplants are onion plants started from seed. Sets look like small onions that are typically second-year plants.
Some people feel you should stay away from sets as they tend to bolt easier because of the dry state they’re in at the time of planting.
However, some people feel onion sets are the best way to ensure you receive a full-sized onion at harvest.
This is a personal preference, but a decision best made up front when deciding to grow onions. Give this decision consideration before starting your crop.
2. Separate Plants from Seed at the Right Time
Should you go with onion seeds, you may start them in the ground or in a container. If you grow them in a container, choose nutritious, well-draining soil to plant in.
I like to use a foil, disposable lasagna pan. Then sow the seeds thickly in the soil. Once the seedlings are approximately four-inches tall, separate them into growing trays.
This method of starting onion seeds ensures the seedlings stay moist which is critical in avoiding bolting.
3. Pick Onions Based Upon Your Growing Location
Were you aware there are different types of onions? You have short-day, intermediate-day, and long-day onion varieties.
Short-day onions form bulbs when the days are between ten and twelve hours long. Intermediate-day onions form bulbs when the days are between twelve and fourteen hours long.
Long-day onions form bulbs when the days are between fourteen and sixteen hours long. What does this mean for you?
Short-day onions typically do best in southern regions. Intermediate-day onions do best in the middle region and long-day onions do best in northern regions.
Understanding this can help you decide which onion variety would work best for your growing location, but planting the wrong type of onion for your area could have a negative impact on your harvest.
4. Transplant Onions at the Right Time
The next thing some gardeners miss the mark on is transplanting their onions at the wrong time. Onions are cold hardy crops.
Therefore, it’s best to transplant them while frost is still occurring. It’s best to transplant your onions one to two months before the final frost date of spring.
This means you should start your onion seeds indoors eight to ten weeks before the final frost date. If you plant too late, this could dry your plants out and encourage bolting.
5. Provide the Right Growing Conditions
Next, ensure you provide the right growing conditions for your onions. This is important to encourage healthy plants.
Onions need a growing area with full sunlight. This means the plants should receive eight hours of direct sunlight per day.
The soil they grow in should be loose and well-draining. This will allow the roots of the plant to receive the moisture they need but not left in an oversaturated state.
Plus, loose soil will allow the onions to fill out. If your growing location has dense soil, be sure to amend it prior to planting.
Finally, be sure the onions are planted one inch deep and four inches apart. There should be eight inches between each row of onions.
By providing the right growing conditions, it should encourage your onions to be healthy and full at the time of harvest.
6. Don’t Forget to Fertilize
Onions are heavy feeders. If you don’t supply the right nutrients and enough of them, your plants may not be successful.
Therefore, be sure to provide fertilizer that’s high in phosphorus at the time of planting. Then three weeks later provide a fertilizer that’s high in nitrogen.
Feed the onion plants once per month until the bulbs begin to form. Once you see bulbs, don’t apply anymore fertilizer to your onions.
By supplying the nutrients needed in the early stages, your onions should have what they need to produce as anticipated.
7. Water Onions Correctly
Some people don’t realize that there’s a correct way to water onion plants. When you plant onions, you should water them deeply at this time.
You should also be sure to water your plants after each application of fertilizer. Outside of these times, onions should receive one-inch of water per week.
Be sure to water the plants deeply to encourage a strong root system. Should the leaves of the plants turn yellow, it means you’re overwatering. Reduce the amount of moisture being supplied to the plants.
When you see the tops of the onion plants shriveling, it’s time to stop watering the plants all together as you’re nearing harvest.
8. Harvest at the Right Time
There’s a right time to harvest onions as well. Don’t harvest them until the tops have died back. Once this occurs, mark it on your calendar.
One week after this marked date, it’s time to harvest them. When the plants are ready to harvest, use a spade to loosen the soil around the onions.
Gently pluck them from the soil. Be mindful not to damage the bulb during the harvesting process as this will encourage rot in the long-term.
9. Know Which Direction to Plant Sets
Should you decide to grow onions from sets, it’s vital that you plant them the correct direction in the ground.
You’ll notice onion sets have a pointed end. You might think this end is a tip and should be pointed towards the ground.
This isn’t the case. The pointed end should be pointed towards the sky. Otherwise, the plant will grow away from the sunlight which will lead to the plant’s demise.
If you grow onions from sets, pay very close attention to this small detail as it can make all the difference in your gardening experience.
10. Don’t Toss Your Bolted Onions
Sometimes onions bolt even if you try everything to keep this from occurring. Should your onions bolt, don’t toss them.
Instead, harvest them. These onions should be the first onions you utilize. Instead of wasting onions or growing discouraged, just put these smaller onions to good use around your kitchen.
11. Preserve Onions Correctly
One of the biggest mistakes gardeners make with onions is not storing them correctly. It’s sad when you’ve put a ton of effort into your onions and collected a nice harvest only to lose it.
With this in mind, let’s discuss how you can properly store onions. The first thing you must do is shake the dirt off the newly harvested onions.
Then find a dry location with adequate airflow to allow your onions to cure. I like to place a pallet in our barn and lay the onions out there.
This provides protection from moisture, the pallet keeps the onions off the ground which avoids rot, and the slight elevation allows for air to flow around the onions. In approximately seven days, the onions should have cured.
From there, store them in a dark, dry location to utilize them in the coming months. You may also purchase onion bags and hang the onions. Some people like to braid onions as well.
12. Don’t Forget to Provide Adequate Care
Our last mistake to avoid is neglecting your onion plants. Onions have very specific needs that must be met. We’ve discussed fertilizing and watering. However, you should be sure to mulch around your onion plants as this helps them retain moisture.
It’s also important that you keep their growing location free of weeds as this creates competition for your onion plants.
Last, it’s important to rotate your onion crops each year. This will help keep disease and pests under control.
However, should you spot an issue with pests or diseases, be sure to act quickly before too much time has passed and your harvest is damaged.
These are the mistakes that gardeners frequently make when growing onions. Yet, if you supply the needs of these plants, protect them, and store them correctly, you might find that onions are one of the easier crops to grow around your garden.
Whether you’re trying to grow more of your own food or save money, growing onions in your home garden could be a simple way to take steps towards being close to your food and saving money as well.