Helianthemum nummularium in bloom
(Photo courtesy of NetPS Plant Finder)
Plant Height: 6 inches
Flower Height: 8 inches
Spacing: 15 inches
Hardiness Zone: 4a
A charming variety for the rock garden, gravel scree, alpine trough, or as edging along a sunny walkway; spectacular bright yellow flowers appear in late spring through mid summer above glossy foliage; lightly shear after blooming; must have good drainage
Common Rock Rose is bathed in stunning yellow cup-shaped flowers at the ends of the stems from late spring to mid summer. Its glossy narrow leaves remain dark green in color throughout the year. The fruit is not ornamentally significant.
Common Rock Rose is an herbaceous evergreen perennial with a mounded form. Its relatively fine texture sets it apart from other garden plants with less refined foliage.
This plant will require occasional maintenance and upkeep, and should only be pruned after flowering to avoid removing any of the current season's flowers. It is a good choice for attracting butterflies to your yard. It has no significant negative characteristics.
Common Rock Rose is recommended for the following landscape applications;
Planting & Growing
Common Rock Rose will grow to be only 6 inches tall at maturity extending to 8 inches tall with the flowers, with a spread of 18 inches. When grown in masses or used as a bedding plant, individual plants should be spaced approximately 15 inches apart. Its foliage tends to remain low and dense right to the ground. It grows at a medium rate, and under ideal conditions can be expected to live for approximately 7 years.
This plant should only be grown in full sunlight. It is very adaptable to both dry and moist growing conditions, but will not tolerate any standing water. It is not particular as to soil pH, but grows best in poor soils. It is somewhat tolerant of urban pollution. This species is not originally from North America. It can be propagated by division.
Common Rock Rose is a fine choice for the garden, but it is also a good selection for planting in outdoor pots and containers. It is often used as a 'filler' in the 'spiller-thriller-filler' container combination, providing a mass of flowers against which the thriller plants stand out. Note that when growing plants in outdoor containers and baskets, they may require more frequent waterings than they would in the yard or garden.