Q: I am considering having a street light installed by the edge of my property. However, it would be near a perennial flower bed I have. I think most lights that the electric companies install are now sodium vapor type (orange light). I heard somewhere that the old mercury vapor lights kept flowers from flowering due to the elimination of darkness and/or the wrong kind of wave length (or color). What wisdom can you share on the effect of street lights on flowers?
A: I have no wisdom at all but I posed your question to Dr. Paul Thomas, official Wiseacre of the University of Georgia Department of Horticulture. His response: “There will be no effect because most perennials are long-day plants. They are not affected strongly by wavelength differences…or light level at night. Let that little light shine!”