On 23 Dec 2017 14:32:27 GMT, David wrote:
We have a Christmas Cactus and the leaves have turned red.
Searching suggests that it is due to too much direct sunlight, too much
water, too little water or possibly something else.

One striking thing is that a leaf which broke off has been rooted in the
same pot and at the moment is growing strongly and is a bright green
colour.

The cactus was growing strongly and flowered about a month or so ago. Now
it is looking less healthy but then these plants often do.

At the moment it doesn't seem to be over watered.

It is in a south facing bathroom window behind frosted glass so I don't
think too much sunlight (at this time of year) is the problem.

A branch broke off, and I've planted that in an adjacent pot just to see
what happens.

One of ours has always been red one of the others has red edges. That
said, they both spend the summer out in the garden and do get sun.

--
Regards
Bob Hobden