Repotting Calla lily

Hi, I've had a pot with Calla lily's in for around 3 years. It's the original pot they came in. This year has been the best display yet with lots of new growth but its beginning to look cramped. Just wondered if I should repot, is general compost ok and when is the best time.
thanks in advance.

 

I did mine in John Innes no.3 mixed with about 25% horticultural grit and they flowered well. Id wait till they die down though or maybe even do it next spring before they wake up. Mine was the other way round. They got too big for the pot so I split them to make 2 plants. Maybe someone else can give you better/different advice. Overall though Im a bit disappointed with Callas as they dont last long enough for my liking. I was considering putting them in the ground but decided against it because of the watering plus my soil is very clay laden.

 

Thanks for replying @ThePlantAssassin. I'll wait and might try to divide them then. Yes I know what you mean. To be honest I give them very little attention. They stay where they are all year and flower over a couple of months. They wouldn't survive in my borders either so they'll have to stay in a pot