Posted: 28/07/2013 at 22:20
Lottie, you will need to feed them in a pot. You can use the special clematis feed from garden centres, or I push a few osmacote slow release pellets in every spring. I lined my pots with bubble wrap to keep the roots cool. I would also mulch with gravel to shade rather roots - planting euonymus will just be one more thing competing for water and nutrients in a pot.
i have had patio clematis in pots for 3 years now. Every spring they get cut down to 6 inches and they always cover their wigwam and produce loads of flowers by about June.