Hydrangea arborescens 'Haas Halo' (smooth hydrangea)

'Haas Halo' is a cultivar of smooth hydrangea that is distinguished by its upright growth and oversized lacecap flowerheads. It was rated a top performer in Mt. Cuba Center's hydrangea trial, which evaluated 29 species and cultivars of Hydrangea arborescens and two related native hydrangeas. This cultivar blooms from mid-June to early July and grows to about 7 ' tall and wide, with 8" blooms. It will grow best in moist to occasionally dry soil in full to part sun. Also can thrive in shade, with flower heads remaining attractive for months after their midsummer bloom. It is believed to handle the heat and humidity better than some other smooth hydrangea cultivars. Can be cut back in  spring to reduce the plant's height and magnify the floral display.

'Haas Halo' is a strong pollinator attractor. This cultivar was in the top 5 pollinator attractors in Mt. Cuba Center's hydrangea trial. Its lacecap inflorescences contain hundreds of tightly grouped, readily accessible fertile flowers, each containing pollen and nectar rewards for bumblebees, small wasps, bees, beetles, true bugs, and flies. (Butterflies are less attracted to hydrangeas.)

Photo credit Michelle Dorsey Walfred, licensed under Creative Commons.