A few weeks ago, I bought a potted chrysanthemum in a supermarket. Having bought cut blooms and noticed they stay good for weeks with changes of water, I expected that this potted chrysanthemum would last a lot longer, but now the flowers are turning brown.
The pot is kept indoors, near to a window - not on a windowsill because they're not wide enough, but on a table right in a small bay window (the curtains are open usually during the hours of daylight). We water it about every 3 days (when it feels dry and is starting to droop slightly). There is a radiator in the bay window and now that winter's hitting, us (I'm in London, UK, so the daytime temperature is about 10-14) it's on for a while in the morning and usually most of the eveing.
Is it just that the flowering season is over now or are we under-watering and/or over-heating it? If it is getting to the end of the flowering season, what should I do with it now? I have read that they're perenial, so I'd hope to be able to revive it next year and possibly split it to get more plants from it.
Any advice or help would be very gratefully received.