As I’ve mentioned before, onions are one of my favorite things to grow. They are simple to plant, super easy to maintain, and if you harvest and cure them correctly you’ll have onions for many months to come.
But harvesting and curing them correctly is key for longer-term storage. If you aren’t growing many onions and plan to eat them immediately after harvesting, feel free to skip the curing process. But if you grow more than you can eat in a week (like I do), be sure to follow these steps otherwise that large harvest will not make it very long and they will be wasted.
Before I jump into some instructions for harvesting and curing onions, here are a few things to note about these delicious garden delights.
Flowering/bolting onions cannot be cured for long-term storage. While the flowers that onions send up are rather stunning (and look gorgeous in a vase on your table) it’s not a great sign. There are several reasons onions may bolt such as temperatures in their early life stages, but the good news is they are still edible…including the flower! You’ll just want to be sure to eat them right away since it won’t last as long as ones that have not bolted. If you have a few, just hand out some to your friends and neighbors. Or you can try and leave it in the ground and see if they come up next year (I haven’t had good luck with this option…but it’s worth a try!).
Sweet onions supposedly cannot be stored as long. Although I only grow sweet onions and last year they lasted for almost the entire year. A few started shooting up sprouts/sets, but mostly they didn’t last an entire year because I ran out. But it’s good to keep in mind nevertheless.
In central Texas onions are generally ready to be harvested the end of April through the month of May. This spring has been unusually cold so I am just now getting to harvest my onions. Last year they were all out by the end of April. If you live outside of Texas, ask around for your local harvest dates.
Now for the harvesting and curing onion steps…1 Timing. Once your onions start bulbing keep an eye on your plants. They will let you know they are ready to harvest as soon as the tops flop. I love this about onions because it keeps the guesswork to a minimum.
It’s okay if you can’t harvest them immediately after the tops flop over. In fact, I recommend leaving them in there for a couple weeks after they do. If you want to harvest all your onions at the same time you can push down the tops of the slower onions yourself so they are all on the same “schedule.” I like to wait until they all flop over themselves, but it is definitely up to you.
You’ll also want to stop watering them at this time (if it rains it’s not the end of the world so don’t fret). This helps kick-start the curing process.
Some onions I believe you can even keep in the ground until the temps drop, but you can’t do this with sweet onions. Plus, I like to get them out of the ground so I can plant something new in their place.2 Harvesting. After your onions have flopped over and they have had the chance to dry out for a week or two, it’s time to get out there and start pulling them out.
It’s recommended to harvest your onions on a dry and sunny day. Carefully pull them out by their neck being carefully not to knock them together so they bruise. At this stage they are still really tender and not like store-bought onions so treat them gently, like you would do with a bunch of eggs.
Optional: You can gently rinse the dirt off the onions at this point in time, but it’s definitely optional (especially because some onions don’t hold on to a ton of the dirt when harvested). Just fill a bucket with water and gently rinse the onions in the water. Again keep in mind that the onions are super tender so gentle is key.
Once you pull them out lay them out in the garden or somewhere the roots can dry out for a couple days to a week. A sunny spot will dry them out quicker so I usually spread mine out in a single layer on our patio table.3 Curing. Once the roots have dried out for a couple days the onions will need to move to a shady spot with good ventilation for two to three weeks to finish curing.
At this time I usually trim the roots and stems since they are not necessary for curing and it makes them easy to move to storage later.
Some people cure the onions in a warm, breezy spot on their shady porch or in a shed with good airflow. I usually keep mine on my patio table and top it with a laundry basket since my back porch doesn’t have a completely shady spot. This keeps it in the shade and provides great ventilation.
Again, they will need to be kept here for 2-3 weeks until they are dried out. I usually keep an eye on the tops of where I cut the stems off and if they are all dried they are ready for long term storage.4 Storage. After 2-3 weeks have passed and the onions are dried out, they can be put away for long-term storage.
Onions need to be stored in a cool, dark, dry and well-ventilated place. It is recommended to store them between 35-45 degrees. A basement, storage shed, or pantry can work great depending on how hot it is where you live. You will also want to make sure not to place too many onions in one storage bag or basket in case one did not cure correctly and it starts to go bad earlier than expected.
I like to store my onions in several mesh, reusable produce bags and place them in my pantry or even my refrigerator. Side note: If you plan to replant some of the smaller onions for the next year, storing them in the fridge is not recommended as this could encourage your onions to bolt the next season.
If you follow these steps carefully, you should be enjoying your onions for months to come! I know I will be out in my garden this weekend and starting the harvesting and curing process for the 200+ onions I planted this year. It’s about to be onion central at my house!
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