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Why Do Onion Sets Go Soft

Onion sets are the easiest and most recommended way to grow and plant onions. Onion sets are onions picked prematurely to save and plant them the following year. Onion sets store extremely well and can easily be stored for a year for the following season. 

Sometimes, if onion sets aren’t stored properly, they will become soft and get slimy or mushy and brown or black spots. While you can still plant onion sets that appear to be a bit moldy, you shouldn’t plant onion sets that feel soft or mushy. 

In today’s article, we will be talking about soft onion sets, why they happen, if they can be fixed, and more. Stick around.

Soft Onion Sets

There are a few reasons why onion sets go soft. Sometimes, it’s a disease that reaches the plant while they are still in the ground and doesn’t strike until they are being stored. Other times, it’s because they aren’t stored correctly. Let’s go into further detail. 

Onion Soft (or Neck) Rot

Onion soft rot of onion neck rot is a common bacterial disease that starts at the neck of the onion. It will look like mold at the base of the onion neck, then slowly take over the entire onion set, making it look as though it has a water stain. The insides of the onion set will begin to feel mushy and soft. 

Onion soft rot can start while the onion is still in the ground, caused by moisture or even transferred through seeds. However, the disease will not show symptoms until the onions are stored. Once you see onion or some onion sets appearing to have soft rot, remove them from the other immediately to stop anything from spreading. 

Poor Storage Conditions 

Besides soft onion rot, you may have storage conditions that aren’t ideal for onion sets, causing them to go soft. As we mentioned above, onions need a dark, cool, and dry place to be stored if you want them to last a while.

Having dry conditions is probably the most essential part. If any moisture is on the onion sets as they are being stored, it will cause mold, which will cause onion sets to go soft. 

Can You Plan Soft Onion Sets?

You must first determine if the onion sets have soft onion rot or if the conditions weren’t right. This is important because if it’s soft onion rot, it should never be planted. Rather, they should be thrown out immediately if you don’t want the disease to spread. 

If it isn’t onion soft rot and you feel your storing conditions just weren’t perfect, then here is what you can do. Inspect your onion sets. Are they just starting to mold but still feel firm on the inside? You can still plant them at this point, and you will probably want to as soon as possible. If your onion sets look moldy and feel soft and mushy on the inside, they can not be planted. 

How To Store Onion Sets

If you want to avoid mold or rot while storing your onion sets, then you should make sure you are storing them perfectly. Here is how you can do so. 

Mesh BagsMesh Screens
Mesh bags are the easiest and 
most common way onion sets are stored.

Mash bags can be found at any garden
store or hardware store, or online. They 
are usually made from nylon or polyester
and vary in size.

The purpose of the mesh
is to allow the onions to breathe
properly as they are being stored.

They are also hung up and make for easy
out of the way storing.

Depending on how large your mesh bag is, you
can fit multiple onion sets in the bag. 
You don’t want it overcrowded though. 

Simply place the onion sets into the mesh
bag, tie it tight and hang it up in a cool,
dark, dry place until you are ready to plant
them. 
Mesh screens are another option for 
storing onion sets. Mesh screens are
handy if you have a lot of onion sets 
because you can get very large mesh
screens that will hold lots of onion
sets. You will want to place your mesh
screen over something to hold the 
onion sets, while still allowing them
to breathe. Place the onion sets on the
mesh screen in one layer, make sure 
nothing is overlapping each other. Store 
in a cool, dry, dark place. 
Ways to store onion sets to prevent softening

Remember that while you need a cool-ish environment to store onion sets, never store them in the fridge. Refrigerators are too cold for storing and will cause the onion to ripen and go soft or mushy. If you do store them in the fridge, you should plan on using them within one week. 

Final Thoughts

Onion sets are extremely easy to store; however, they sometimes appear to mold and get soft. Usually, this happens because the storing conditions aren’t right. Maybe it’s too cold, or maybe some moisture got into the onions.

Whatever it may be, proper storing conditions are extremely important for saving onion sets for a long time. You also have a bacterial problem on your hands, so you must get rid of the infected onions immediately. Happy gardening!