"Candida" means brilliant white, and that's exactly the color of this native western United States wildflower.  Sometimes also called "wild hollyhock," it grows to three feet tall, with stalks filled with one inch flowers, each with five petals.  It blooms from June - September in full sun/partial shade in well-drained soil.  I am not certain of Zones yet, but these came through winter in Zone 6 with no problem.  Quarts.