|We were told by a florist that we needed to keep bright lights on our Poinsettias 24 hours a day during the Christmas season. We normally have 10 500w mercury vapor lamps lighted for 8-15hrs a day. During the Christmas season this year we added over 10,000w of tungsten lights.
This seems excessive for 24hours per day. What is the definition of "bright" light for Poinsettias and for how long during a 24 hour period?
|Since it sounds like you are producing these on a commercial scale, I would strongly suggest you contact your local County Extension (840-7408) for assistance in determining the best and most efficient lighting arrangements for your poinsettias. (This can depend on a multitude of factors such as temperature and fertility as well as the type of lighting used so it is best to take an overall look at the growing conditions and plant quality.) In general I would concur that lighting the plants for 24 hours a day is excessive -- they need that regular period of darkness to complete their own internal cycles so 16 to possibly 18 hours of light would be about the maximum where you would gain anything.|