Saturday, June 18, 2011
Myrtle-leaved St. John's-wort - Hypericum myrtifolium
Myrtle-leaved St. John's-wort (Hypericum myrtifolium) has foliage that looks somewhat similar to that of four-petal St. John's-wort (H. tetrapetalum), but the flowers of this species have five petals. Myrtle-leaved St. John's-wort is a wetland species; found in a variety of locations nearly statewide. It is confined to the Deep South and occurs only in nearby states -Alabama to South Carolina.
This is an evergreen woody shrub that may reach about 3 feet tall. The branches are thin and the plant has an irregular aspect. The opposite leaves clasp the stems, are triangular in shape and blue-green in color. This is one of many species in this genus to have exfoliating bark. In mature specimens, it peels away from the main stem in noticeable sheets.
Flowering is confined mostly to the spring. Individual flowers are showy. The five petals are a rich yellow color and the mass of pollen-producing anthers add to their interest.
In my experience, this species requires wet soils to prosper. Plants I have used in my Pinellas County landscape have failed when planted in soils that sometimes dry out for more than the briefest of periods. If a wet area is available, however, this is an extremely showy species that does not take up too much space. Regrettably, it is only rarely offered by commercial nurseries for the home landscape. Should you locate a source, use it at the edge of ponds or shallow wetlands. Plant it in mass as individual plants are rather thin and to take advantage of its showy blooms.