Q: When a plant tag says full sun or partial shade, how many hours of sun or shade are appropriate when determining if a spot is suitable for the plant?
A: Sunshine intensity differs across every landscape and garden. Compare the noon sunshine in Valdosta to noon sunshine in Blairsville: they’re radically different. In any area, afternoon sun is stronger than morning sun. This is how I judge sunshine conditions in different parts of the state:
Coast: unfiltered sunshine for 6 or more hours per day
Mountains: unfiltered sunshine from morning to night
Elsewhere: unfiltered sunshine for 8 or more hours
PART SUN/PART SHADE
Coast: all day sunshine filtered through high pine or hardwood (oak, maple, poplar, etc.) foliage OR 3 hours of direct sunshine between sunrise and noon, followed by shade
Mountains: five hours of direct sunshine between sunrise and noon, followed by shade
Elsewhere: direct sunshine part of the day, or partial sun (as under high pine trees) all day.
Coast: all day shade under low evergreen trees (live oak, magnolia)
Mountains: occasional direct sunshine during the day or dappled shade under low deciduous trees (dogwood, redbud, crabapple, etc.)
Elsewhere: dappled shade (as under low and high hardwoods) all day.