What's wrong with my Calathea?

Question

We've had this plant ~6 months in the UK, it usually lives in the bay window so gets lots of sun. However, the edges of the leaves started to go brown, despite twice-weekly watering and reading online, it might be because it's getting too much sunlight.

We moved it away from the window for a few weeks, and it's still seems to be slowly dying. As you can see from the photos the edges of the leaves are browning, and the underside is off-color. We must be doing something wrong, any suggestions?

Edit: we've also been misting it with water daily to try and increase the humidity

Answer 1

It may be too late to save it - putting it in a window which gets direct sun would have caused the plant significant problems. These are not easy houseplants to keep - they need high humidity, bright light but no sun, do not like to dry out but also don't like their feet sitting in water in any outer tray or pot.

You could try to keep it going and maybe help it recover - find a tray which is bigger than the pot, fill it with pebbles, then add water to about halfway up the pebbles and stand the plant on top, in the middle. Keep the water topped up - this is not intended to water the plant, in fact, the plant should be kept clear of the water, but it will provide more humidity. Cut off badly damaged leaves at the base, and stand it somewhere with bright daylight but no sun. Water when the surface of soil feels just about dry to the touch, water thoroughly, allowing any excess to drain away freely from the base of the pot - best to remove it from the pebble tray while it drains down. Further information here https://www.ourhouseplants.com/plants/calathea