Q.How to care for Christmas cactus?
I put my Christmas cactus out on the deck (it has a roof but gets morning sun) and while the plant seems to be growing, the new growth is red. Is that normal? And how much water does the plant need?

Certified GKH Gardening Expert
Normally, these do not do well in full sun. It is also necessary to use epiphyte soil, as these will not do well at all in regular potting soil. The red coloration could be due to it getting full sun.
This plant will fare best as a houseplant. I would move it indoors to a bright location. Window light is ok, since your windows will filter out quite a bit of UV light, which is what really harms the plant.
As far as watering goes... They like slightly moist soil. They don't like it dry, and they don't like it sopping wet, so a balance is necessary.
This article will help: https://www.gardeningknowhow.com/ornamental/cacti-succulents/christmas-cactus/advice-for-christmas-cactus-care.htm