Looking after an orchid

Can you help please? I have a beautiful phalaneopsis orchid which has been happily flowering on a window sill for four years - it's on it's third lot of flowers. The leaves have begun to die back from the tips, going brown and shriveled, and there are now only two leaves left, which are brown down half their length while the three large stems are supporting over 30 blooms which seem OK.
I re-potted it last spring when it had died back, and until the late autumn it seemed happy.

1. What soil did you re-pot the Moth orchid in?

2. Does the temperature in the room go beneath 18 C at night or is it standing in a cold(er) spot?

3. What is your watering regime?

4. A clear photo could clarify a lot

I re-potted it in 'orchid compost' from a reputable garden centre.

The temperasture may have dropped below 18 c at night in the period that the leaves started to go brown.

I water when the compost feels dry, but not more than once a week.

Hi Lisa,

To me, it looks like the leaves have been badly scorched by sunlight, earlier in the year. I have had the same with my Moth Orchids because mine are standing on a window sill facing south-east where they get too much direct sunlight. They need lots of indirect sunlight, so a sill facing east or west would be best.

You have repotted it correctly and is otherwise looking very healthy. After flowering a new leaf usually appears.

Instead of watering once every week I would be inclined to mist one week and water another week until it gets warmer and brighter again. Water temparature should be lukewarm and preferably no tap water. When the roots are still green, no watering is needed. Hopefully the orchid will recover soon.