When to Harvest Red Onions
When it comes to harvesting onions, yellow and red onions show the same signs. Check your onions for the following signs, and then cure your red onions:
- Large mature onion bulbs
- Onion necks break
- Onion tops turn yellow and tip over
If your red onions sprout a flower at the top of the stalk, pick them right away. These onions do not do well in storage, so use them right away. You can also peel them, dice them, and freeze them for later use.
How to Cure Red Onions
Once the red onion tops fall over, it’s time to cure your onions for harvesting and storage. All you need to do is pull or dig the onion bulbs out of the soil, and allow them to dry out right in your garden for a couple of weeks. You want to let them cure until the stems and roots are dry and crispy.
Once the onions reach that point, gather them from your garden. Trim off the excess roots. If you’re planning to braid your onions stems together for hanging, leave the long, dry stems attached to the onion. Otherwise, trim off the dried stems.
Storing Red Onions
After your onions dry out completely, sort through them, and pick out any onions that have bruises, cuts or feel soft. The reason for this is that you don’t want any moisture to transfer to your dried onions during storage.
After sorting, place your onions in containers that have good air circulation, such as mesh bags, slatted crates or wire baskets. If you braided your red onions together, hang them in your storage area. Store the containers in a dry area that has consistent temperatures of 32ºF (0ºC) to 40ºF (4.4ºC). The humidity in the storage area should be around 70 percent.
If you use a shed or garage for storage, keep track of the temperature. If your forecast predicts freezing temperatures, move your onions to a warmer location.