‘Gemo’ is a cultivated variety of our native Kalm’s St. John’s-Wort (Hypericum kalmianum). This selection is more compact and tightly branched than the species, making it a very tidy, uniform, and well-behaved addition to any garden. It is more floriferous as well, with radiant yellow flowers in abundance starting in June and carrying on through July and August with sporadic blooms until October. The narrow, willow-like leaves are bluish-green all summer and do not usually provide appreciable fall color, but their deciduous nature reveals the interesting peeling bark of the trunks in winter.
‘Gemo’ looks especially good planted in masses along pathways, in foundation plantings, as a low hedge or backdrop to other small perennials. It is a carefree, low-maintenance shrub that looks good year-round and is very undemanding.
*This is not the species renowned for its medicinal properties, which is the non-native, invasive Hypericum perforatum.
Sources:
Manual of Woody Landscape Plants by Michael A. Dirr
Chicago Botanic Garden
