Is Moving Our Croton And Mandevilla Indoors And Out Detrimental?

Q: My wife and I are having a debate. I take our croton and mandevilla outdoors when the temperature rises above 40 degrees. She wonders if moving them in and out is detrimental? 

A: I think your wife is right. Many of the physiological processes in a tropical plant slow down greatly at temperatures below 55 degrees. I think you should leave your plants indoors unless it’s warmer than 55 degrees outside.