Aster Divaricatus -25 seeds HP. Aster Divaricatus is an upright, bushy perennial to 60cm with heart-shaped basal leaves. Small white flowers with pink to yellow centres are borne in flat-topped clusters on erect, black stems in late summer and autumn. Grow in full sun or partial shade in a moderately fertile, well-drained soil.Seeds are supplied in grip-seal bags.