This is my starting point. A few sedums, hostas, lady's mantle and astilbes in various stages of growth.
The soil is dry and leaves and pinecones need to be raked up.
All raked up.
I wash up the pots with soapy water, but I like the aged pot look so I don't use bleach.
I loosen the dirt, dig any weeds in the area, and line up the little pots first. You can stick a piece of bark mulch under one side if the pots don't sit straight.
Gradually the pots get larger and larger until they reach the rubber edging on the deck plantings.
After the perennials fill in a little more, I will add a few annuals if necessary. Usually, the perennials pretty much fill it up.
If you have run out of ideas for flower bed edging try terra cotta pots!