Ward, D.B. 1979. Rare and endangered biota of Florida. Presses of Florida. The tiny polygala occurs in the pine rockland habitats of southern Florida. Limestone erosion results in frequent solution holes and jagged surface features.
Many plants root in limestone crevices.
Large numbers of endemic rockland plants occur in the understory. Polygala smallii occurs entirely within pine flatwoods in residential areas. The plants occur specifically in the herb layer of these habitats and appear to require periodic burning to prevent overshading by other species. Polygala smallii occurs in open portions of the habitat on dry, sandy soils composed largely of Pamlico sands, with no horizons, little or no humus, and a depth of 5 to 10 cm. Associated species such as Serenoa repens, Quercus pumila, Crossopetalum illicifolium, Randia aculeata and Croton linearis, etc. are found growing with P. smallii.