Thank you all for giving me valuable tips about my citrus trees. I think my growing zone is 8 but lately winters have been very harsh, ice n snow n temps below 20*. My greenhouse is very small just enough for my 3 trees so I can't really put heaters n fans as I want. But I understand about leaving the heater on during the night since it gets colder then,but I don't want to start a fire if I leave heater on for many hours. That's why I cover them w/ blankets n then heat the area for short periods of time. By the way I trim my trees before I put them in greenhouse so they don't touch in case there may b white flies, which I did have last year. That was quite a job to get rid of! If anyone has more suggestions on how I can keep my trees healthy n growing in winter I thank you in advance. They're potted not in the ground.
