Factors that govern the germination of cutleaf groundcherry (Physalis angulata L. # PHYAN), smooth groundcherry [Physalis virginiana var. subglabrata (Mackenz. and Bush) Waterfall # PHYSU], and eastern black nightshade (Solanum ptycanthum Dun. # SOLPT) were evaluated. Maximum germination of all three species occurred at a constant 30 C or alternating temperature regimes that included 30 C. Seed of all species germinated in light and dark, but germination was reduced in the dark. Germination and seedling vigor of all species decreased as substrate pH decreased. Cutleaf groundcherry seed were slightly less sensitive than seed of other species to simulated moisture stress. All species produced 90% or more viable seed by 8 weeks after anthesis.
