At present there are over 200 named cultivars of Helianthemum nummularium available for sale, some more widely available than others.To maintain this wide selection, cultivars need to be continuously propagated using one of the included propagation methods, either from seed or by cuttings. Propagating from cuttings ensures an exact copy of the parent plant is maintained. Plants from seeds can produce some very interesting forms due to cross pollination.
The majority of Helianthemum’s are propagated from cuttings as this is the quickest, easiest and method with the highest success rate to produce new young plants. With propagating from seeds, germination rate tends to be low and seeds, particularly with Helianthemum cultivars are difficult to collect. Despite not collecting any seeds formally, we have found some self-seeded unique plants produced through cross pollination.
The following sections will suggest how to propagate plants from cuttings or seeds; however there are many alternative methods which may be equally successful.
Collection stock plants can survive up to 20 years, however many become very woody after approximately 5 years and should be continuously replaced. Plants are also lost from time to time particularly in cold, wet and damp winters. Therefore it is very important to continuously propagate and replace stock plants.