RHS names best-performing plants in new AGM list
19 February 2013
A display celebrating the launch of the revised list of Award of Garden Merit (AGM) plants at the RHS London Plant and Design Show, 19-20 February, forms the centrepiece of exhibits in the Lindley Hall.
The display features a range of exciting plants included in the new revised list of 7,000 plants that have been recognised by the RHS as being outstanding in cultivation.
Plants on show include hardy ornamental winter-flowering shrubs in full bloom, such as Daphne bholua ‘Jacqueline Postill’, above, with its deliciously scented displays of pink flowers. Edible plants were also featured, including popular and easily grown Rhubarb ‘Timperly Early’, and some houseplants such as Streptocarpus ‘Crystal Ice’ which reliably produces masses of appealing blue and white flowers over a long periods.
Newcomers to the revised list are tender orchids, included for the first time since 2002. Some 34 have been added, selected for being easily grown even by non-specialists, and consistently available true to name. On the stand was beautiful white-flowered Cymbidium Sarah Jean ‘Ice Cascade’.
The list was launched by plantsman and co-ordinator of the 2012 AGM review, John Grimshaw, who summed up the review ‘This has been a highly exciting process, leading to the best possible selection of recommended plants for UK gardeners, as tried and tested by the RHS.’
The AGM plants have all been recognised for their ability to meet the following criteria:
• Excellent for ordinary use in appropriate conditions
• Of good constitution
• Essentially stable in form and colour
• Reasonably resistant to pests and diseases
• Available to buy in the UK
Potential AGM plants are nominated through two main routes – either by recommendations from RHS Plant Committees and specialists, or as a result of an RHS Plant Trial.
Originally compiled in 1992, the list has been completely reviewed by RHS Plant Committees, whose members include nurserymen and leading horticulturists, with assistance from plant societies and plant-group specialists. The review, which took place during 2012, was led by Dr John Grimshaw, Director of the Castle Howard Arboretum Trust.
As part of the overhaul, all existing AGM plants were reconsidered to ensure that they still met the stringent AGM criteria. Those that fell short were removed from the list, while new awards were made after round-table assessment by relevant committees or during RHS trials.
On 19 February the RHS will also launch its new hardiness ratings. The ratings have been used to reassess all AGM plants by using data on the plant’s ability to tolerate a range of weather conditions. The new hardiness ratings rank from H1 for growing in a heated glasshouse to H7 for the very hardiest of plants, giving gardeners a more useful guide than the former H1–H4 system.
The RHS London Plant and Design Show is held at the RHS Horticultural Halls in London on 19 and 20 February. Tickets are £8 and entry is free for RHS members.