A floor bed (which for all intents and purposes is a mattress on the floor) is pretty much the main ingredient of a Montessori bedroom. While some make the case that you can introduce it as soon as your baby is mobile, most brands market them for ages two and up. (Btw, we love this option from Sprout or this option from Target.) But there are many benefits to this type of setup.
Unlike cribs, which require parents to “manage” the sleep and wake-up patterns of their kids, a floor bed puts the child in charge, allowing them mobility and independence. They can get out of—and get back into—their beds as they please without the help of another person. (Of course, there’s independent mobility with toddler beds, too, but the Montessori-approved floor bed has zero restrictions, and no guard rail.)
The idea is that this freedom of movement eventually teaches kids freedom of thought. When they wake up, they gravitate toward the item in the room they’re most curious about, making discoveries and exploring as they go.