Hi Rozy,
It sounds like you may have hurt the
plant by having it close to the radiator. Sometimes just moving a
plant can hurt it. I would also only water it when the soil feels dry. There are probably many other factors that could have affected it.
I've had several Christmas cacti and had great luck with a few. These were the ones I left in a rarely used room. I don't remember how much light they had--I had a window with a ESE exposure where I kept my houseplants, but also had it hanging at times in a corner where the light was primarily from the south. Watering was usually about once a week, but sometimes it didn't need water.
The first year we were there I was shocked when I went into the room and there was a most beautiful
cactus in full bloom. So I quickly brought it into the living room where it could be enjoyed.
Don't give up. You may not get all the blooms this year, but benign neglect for a year or two should help--but keep away from radiators.
Ann1
