Street Lamps – Any Negative Affect On Perennials or Trees?
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!”
On the other hand, this post shows how very bright street lamps can fool a tree that’s changing color in fall.