Hypericum calycinum Carnival Crowthyp - St. John's wort

Hypericum calycinum Carnival 'Crowthyp' is an elegant shrub with variegated yellow foliage derived from a perennial and creeping St. John's wort known for its robustness and resistance to the most difficult growing conditions. This variety is less vigorous and less invasive. It will brighten shaded and dry areas of the garden where nothing grows, and will tolerate occasional lack of watering if grown in pots. Decorative all year round, this variety offers the same large, cup-shaped flowers in bright yellow with a tuft of long central stamens, and it blooms throughout the summer. Ideal for landscaping an unattractive slope, and difficult and dry areas under trees, it is also a lovely plant that requires no special care for container cultivation.

Hypericum calycinum, also known as Rose of Sharon, is one of the best ground covers for temperate climates. Prolific, even invasive, this perennial or undershrub resists everything, grows absolutely everywhere, and spreads through creeping stoloniferous stems. This plant belongs to the Hypericaceae family, and is native to Turkey. It is a woody and suckering plant, related to the shrubby St. John's wort often planted in our gardens. This variety stands out with a more compact, slower growth, and variegated yellow foliage.

It quickly forms a tuft that is at least 50cm (20in) high and 60cm (24in) wide. It spreads through stoloniferous stems that root upon contact with the ground. After a few years, the resulting carpet can cover several square metres. Its young stems and leaves are tinged with pink-red. Its oblong leaves are irregularly margined with cream-yellow to light yellow on a dark green background. They measure about 4.5cm (2in) in length. The abundant flowering occurs from June to September, earlier or later depending on the climate. The solitary flowers are gathered in terminal cymes. They are composed of 5 bright yellow and glossy petals surrounding a crown of long protruding golden yellow stamens.

Hypericum calycinum Carnival 'Crowthyp' is an excellent plant for difficult, rocky and dry areas or under trees where nothing grows. Robust yet elegant, it will blend beautifully with other intrepid ground cover plants, such as small periwinkles (Vinca minor), bergenias, or Caucasian forget-me-nots (Brunnera). A large sunny slope, a dry and shaded understory, or the base of a hedge are its preferred areas. Those without a garden can grow it in a large planter or flower pot, to adorn the base of taller plants.