I bought this pot already planted from the garden centre. It comes in a shallow plastic pot, with plenty of gaps underneath for the roots to grow through. You just fill your own pot with compost and pop the pot on top. A really simple way to have a good selection of bedding plants. Also, they were reduced, so even better.
That sounds like a great idea! Never seen that, but it sounds as if it's perfect for me. I never seem to be able to dedicate the time required for buying plants for the pots and looking after them!