How do you work out how high your work benches need to be? That depends on a few things.

The first consideration is what you want to do at the bench, are you able to stand? Or do you need to sit down? Are you a wheelchair user?
When you are standing at a workbench you will need to work at a level where your elbows allow your arms to be at 90deg and parallel with the bench surface.
If you are sitting down, or a wheelchair user, your work benches needs to allow your feet to be flat on the floor with your knees at, or below, waist height.

I guess the ideal workspace would have a combination of different height work benches, but that may be out of reach for many.
When designing your workspace list the different types of jobs you will need to do then decide if you need more than one work bench. The best workspaces will make it easy for you to get your jobs done without straining yourself in any way. Gardening is fun!
TIL next time!
*images are AI generated