I was initiated into the wonderful world or native Hypericum species, many being rather ornamental small shrubby plants, some with attractive peeling back, by George Newman of Bedford, New Hampshire. These are first class shrubs that are somewhat neglected in horticulture, but should be grown more often. One of the very best is H. frondosum, and Eastern/Southeastern USA species, often seen in the cultivar 'Sunburst':http://plants.usda.gov/java/profile?symbol=HYFR
It is one of those great all-around plants, a manageable small-medium sized shrub, super hardy in spite of its southerly range, with attractive blue-green leaves all summer, and a profusion of large yellow starburst flowers in summer, and wonderful fall foliar color, and interesting twiggy branching and persistent seed pods in winter.
I'll start by showing the winter appearance and late winter/early spring growth. This plant has been a feature of my "foundation planting" for almost 10 years, it is about 30" tall (75 cm) by about 4-1/2' (135 cm) wide... it could be pruned to be smaller. I leave the seed pods on, as they add some winter interest.
This shrub is the earliest shrub to leaf out here, in late winter each year, but doing so in such a subtle way that it is easy to miss this feature. From afar, the shrub looks completely deciduously dormant, but upon close inspection, it not only has new growth buds but has leafed out with linear scale-like leaves... always a surprise. But it is not until much later in the season, when the leaves actually expand, that the shrub begins to appear to be reawakening.