Looking beyond flowers and plants, of course you can also create a herb garden using your Bay and Box window box.
Chives, mint, parsley, sage and lots of others work really well either as a complete window box or mixed in with other plants. In particular, sage, with its soft leaves is excellent planted in with flowering plants and comes in a variety of colours.
To plant your herbs, make sure the box you are using has drainage holes. Bay and Box window boxes come with two drainage holes as standard.