The species' bud scales are efarinose, ovate to oblong and are long. The leaves form a rosette which have winged petiole that is long. It have even longerleaf blade, measuring, efarinose, puberulous and is ovate to deltoid. The base itself is cordate and subsagittate with irregularmargins, coarse dentate and acuteapex. P. tanneri have long scapes which elongate, long near the fruit part and are farinose toward the apex. Umbels have 1-2 flowers with bracts that are acuminate to subulate and are long from the broad base. Pedicel is as farinose as the apex and is long. The flowers are heterostylous with tubular to campanulate sepals which are long. P. tanneri have an emarginated and lanceolated lobes which are obovate to oblong with a light to deep purplecolouredcorolla which can also be blue or white. Tubes of these species can be long while the limb is wide. Flowers are heterostyly with stamens toward the apex and bloom in May.