The onion sets we planted in March have grown a lot! If you remember, we dug trenches for the sets so they were below ground level. The reason we did this is to give the sets a lot of space to grow larger onions than we have in the past.
The rain moved some of the side dirt into the trench, but in the picture you can see how the white portion of the onion top is starting to show. This is the time to start building up the dirt on top of the onions. You should never see the onion top.
We mixed some soil with compost and piled it up about an inch or so above the the top of the onion itself. The compost will help the onion bulb grow significantly larger. You need to leave the majority of the leaves above the surface for photosynthesis.
In the end our onions met our size satisfaction. Much better than in previous years. Since we found out the hard way last year that the onion sets I was purchasing were considered Fresh, not Storing onions, we will just pull up onions as we need them, or as a customer orders one. We will leave them in the ground and pull as needed until the weather projection calls for more than 3 days in a row in the teens. Onions can handle freezing weather as long as there are some intermittent warm ups. It’s when the ground freezes solid that you have a problem. That usually doesn’t happen unless you are in the teens for at least 3 days. We also put row covers over our plants during inclement weather which keeps the ground from freezing.
I think we finally learned how to grow onions the best way for our climate!