I have one that is a flower bed, made from old railway sleepers.
For the heavy e-bike there are two small flagstones at just the right distance apart set into the bed amongst the flowers, that it can sit there and be washed, leaning against the post..
For gravel/road/mtb I have a single centre post rigged with old road handlebars on top, set securely into the bed, which will hold the bike a few inches off the bed, with the cross bar held by the old road bars. I wash them all there, can spin the wheels etc, and the mud and crap is captured by the bed. Have to lift off and flip to do the other side, but other than that is great, no mess, and water the flowers at the same time.
There is a small bush, a few flowers and a crab apple tree, they don’t seem to mind muc off.