'Haas Halo' Hydrangea Hydrangea Arborescens rose mallow Dimension also stops more than fruit Dimension also stops more than 30 other grassy and broadleaf weeds from invading the lawn and garden beds if applied before the weeds germinate Bronze red leaves emerge in late spring and hold its color well into early summer Its upright bushy form has excellent structure with minimal pruning and its stout sturdy stems keep those massive flowers upright and never flop These tiny flowers offer nectar for beneficial insects and butterflies while the larger sterile flowers around the edge offer a splash of pure white and act as a landing pad in July and August