Hypericum or St. John's Wort is a stunning plant in flower and also a very prolific ground cover plant. Hypericums are also great plants for colour - not only do they produce brilliant flowers, they also bear fruits that are often highly coloured too. Hypericums come in all shapes and sizes (there are over 400 species!) however Hypericum Calycinum or 'Rose of Sharon' is one of the best for ground cover, even on dry, shaded banks. It is a valuable and robust asset to the garden. Hypericums will thrive in sun or partial shade and a well-drained soil. Cut back the stems to the ground annually to improve flowering.