Mushroom mounts are one of the many different kinds of mounts that players can find and use in Lawn Mowing Simulator. They are a fairly rare mount, and can be found by chance while mowing lawns. While they don't offer any particular advantage over other mounts, they are still a cool item to have. Here's how you can get your hands on one:
First, make sure you're playing the game with the latest update installed. The mushroom mount was added in version 1.2, so if you're not running that version or higher you won't be able to find one.
Once you're up-to-date, start mowing some lawns! Any kind of lawn will do - once in a while, while you're mowing, you'll see a small mushroom pop up out of the ground. If you manage to mow over this mushroom with your lawnmower, it'll count as catching it and you'll earn yourself a shiny new mushroom mount!