Prior to the Vidalia onion transplant (where we hand pull & hand re-plant all our Vidalia onions in alternate fields), we trim the Vidalia tops with a large trimming motor attached to our tractor. It resembles a very large lawn mower.
The tractor creeps ahead, moving around 3 mph, allowing the spinning blade to trim 2 inches (or so) off the top. The trimmed tips are ejected to the side and allowed to naturally dry, breakdown, and compost back into the soil.
Why do we trim the tops of our Vidalia onions? Primarily, to strenghthen the necks of the onion, so that they’re able to support the future growth (& weight) of the onion leaves (as they grow over 1 foot long). If trimming isn’t performed, there’s a higher likelihood the leaves will fall over and tear the necks, which damaged the integrity of the onion.
Here are a few snapshots of us trimming the tops of our 2022 Vidalia onion crop:
Before Vidalia onion tops are trimmed
After Vidalia onion tops are trimmed