Phenotypic plasticity of sun and shade ecotypes of Stellaria longipes in response to light quality signaling: Cytokinins

► In shade light a prairie ecotype of Stellaria longipes shows highly plastic growth. ► But, an alpine ecotype of the S. longipes complex gave no growth response to shade light. ► Prairie ecotype plants had mainly trans-cytokinins: trans-zeatin and dihydrozeatin. ► Alpine ecotype plants had mainly cis-cytokinins - which are of low biological activity. ► Growth response differences between ecotypes appears linked to cytokinin profiles.