Q. We have a Christmas cactus that continues to grow but rarely blooms. We have it in a garden window but it is still quite shaded. Do I need to put it in a dark room and water it for a certain period to get it to bloom? Gerri Wilson – Bonney Lake, WA
A. Christmas Cacti blooming is initiated either when they are grown for approximately eight weeks where night temperatures dip to 50-55 degrees, or when they get 13 continual hours of darkness over a period time. Providing both is a grand slam. My Christmas Cacti grow in my sunroom. During the winter months I have a heater with the thermostat set to 40 degrees. This suits the other plants I grow and allows for the cool treatment the Christmas Cacti need to bloom. So if you have a room with a window that you can leave unheated or another space this would work. Other gardeners leave their plants outside for the summer and wait to bring them inside before outside temperatures get below 35 degrees since the Christmas Cacti are not frost hardy. Once the plants have received their 8 weeks of treatment they can be placed back in their normal location and will bloom around the holiday season.