Eupatorium maculatum Atropurpureum Group, late July. Sometimes known as Joe Pye or Joe-pye weed. Many synonyms include: Eupatorium purpureum subsp. maculatum 'Atropurpureum', Eupatorium atropurpureum , Eupatorium fistulosum 'Atropurpureum', Eupatorium maculatum 'Atropurpureum', Eupatorium purpureum 'Atropurpureum', Eupatorium purpureum var. atropurpureum