‘Obsidian’ coral bells, alumroot Heuchera ‘Obsidian’ Type:heucheras (coral bells)Perennials Notable Traits:resistant: deerstriking foliage Hardiness:Zone 4 – 9 Mature Height:8-12in Light:part sun/afternoon shade (eastern exposure)part to full shade (4 hours or less sun)part to full sun (6 hours or more sun)shade (northern exposure)sun (8+ hrs)sun or shade Water:requires regular watering Bloom Color:white Bloom Shape:filler Bloom Time:summer Foliage:black Description The blackest Heuchera you can get. Leaf undersides are deep purple with the same glassy finish. Small, creamy-white flowers appear in late spring to early summer. Larger and more vigorous than ‘Blackout’.