Which plants are in the Scheme and why?
There are 47 plants in the Conservation Scheme at the moment and you may wonder why there are not more and why these particular plants have been chosen.
Thousands of perennial plants have been bred and introduced to the nursery trade over the years. As gardeners we enjoy trying new plants, but know that not all will stand the test of time and may not be as hardy as older varieties or be more susceptible to pests and diseases.
HPS members have a wealth of experience of growing hardy perennial plants and are asked to propose plants they think are worthy of conservation, particularly some of the older cultivars that are hard to find in nurseries or garden centres.
Suggestions are considered against a set of criteria developed from international criteria for conserving endangered wild plants, but modified to make them more appropriate for fulfilling the aims of the HPS Conservation Scheme. Points (up to a maximum of 10) are given for resilience, garden value, historical significance, provenance or breeding potential, horticultural award (AGM or other) and difficulty of propagation.
Resilience means that the plant grows well in a variety of situations and locations, is frost hardy and has good resistance to pests and diseases.
Hemerocallis 'Apple Court Damson' is easy to propagate
but grows too slowley for the trade.
Erigeron 'Sincerity' bred by Alan Bloom
Garden value is judged on the length of flowering or other season of interest (perhaps good foliage colour that lasts for several months), whether the plant has a 'good habit',being easy to grow, but not invasive, and not requiring too much attention over the growing season as well as providing food for pollinating insects.
If a plant is difficult to propagate or slow to bulk up into a clump which can be divided then it is less likely to appeal to the nursery trade although it may score well in other respects.
A plant may be of historical significance if it was bred or discovered by an HPS member, is a distinctive break from other cultivars or has an unusual trait which could be valuable in future breeding.
Over the years there have been many more plants in the Conservation Scheme and many have been excluded after a trial period because they might fail to live up to expectation or have been incorrectly identified. We aim to be rigorous in researching the history of each plant to ensure that it matches a description in a registration database where one exists, or nursery catalogues. Members who participate in the Scheme are asked to propagate plants vegetatively so our stock is not contaminated by inferior seedlings. Some plants have been dropped from the Scheme because they seemed to be growing in popularity but we know that some have failed to compete in a fast-moving market and we would like to bring them back.
We are always looking for plants to add to the Conservation Scheme so if you have a plant that you think is suitable for conservation or have previously grown a conservation plant then please contact me (firstname.lastname@example.org) or your Local Group Coordinator.