Go Retro with These Beauties
Rose-of-Sharon or shrub althea (Hibiscus syriacus) is a frequent denizen of old gardens where it often grows 8 to 10 ft. high and 4 to 6 ft. wide. The toughness and durability of this old-fashioned was eloquently affirmed by Felder Rushing in his 11th book, Tough Plants for Southern Gardens: “A drunk driver once ran over my great-grandmother’s old althea and it came right back with new flowering growth. That’s one tough shrub if it can be pruned with a pickup truck!”
Rose-of-Sharon blooms in the torrid months of July, August, and into early September. Depending on the cultivar, flowers can be single or double in a range of colors that include white, pink, purple, blue and red. The flowers give rise to highly fertile seed pods, which can become a nuisance. I still remember a roadside rose-of-Sharon that I rescued more than a decade ago. I never realized that this single shrub would thank me with bazillions of offspring. Fortunately, there are new, sterile to semi-sterile cultivars that have been selected for their compact nature (older cultivars are prone to legginess) and gorgeous flowers.
Despite the availability of new releases, I’m old-fashioned and like to go retro with these 1970s releases from the U. S. National Arboretum: ‘Diana’ (white), ‘Aphrodite’ (pink), ‘Helene’ (white), and ‘Minerva’ (lavender). These sterile cultivars named after Greek goddesses have compact growth habits, leathery dark green leaves, and produce little or no seeds. Site them and any Rose-of-Sharon in full sun. Since they produce flowers on current season’s branches, prune these deciduous shrubs when they're dormant in late winter, preferably with bypass pruners or loppers – not your granddaddy's pickup.