This is the Royal Horticultural Society symbol for the Award of Garden Merit ‘AGM’. This award indicates that the plant is recommended by the RHS.

Awards are usually given after a period of trial at an RHS garden.

The AGM is intended to be of practical value to the home gardener. It is awarded therefore only to a plant that meets the tried and tested plant varieties using trial methods and  criteria.

AGM Criteria

• It must be available in the UK
• It be of outstanding excellence for ordinary garden decoration or use
• It must be of good constitution – the award includes a hardiness standard – H4 is hardy through out the UK
• It must not require highly specialist growing conditions or care
• It must not be particularly susceptible to any pest or disease
• It must not be subject to an unreasonable degree of reversion in its vegetative or floral characteristics.

Though growing conditions and plant types may vary, the purpose of the award is always the same to highlight the best plants available to the home gardener.

No limit has been placed on the number of plants that may hold the award at any one time. In groups that include many cultivars, standards have to be set especially high if the AGM is to offer helpful guidance to the gardener. The award can be removed.

You can search for AGM plants at RHS sites. Detailed trials reports are usually such as this for carnations.

The Kiro LonKirok ‘was recommended for an AGM by the majority of the members present 6:1. The recommendation was proposed due to the outstanding quality of the flowers, the vibrant colour, form and its ability to provide flowers throughout the year together with a clove scent.’

‘Florence Franklin on the left was not recommended for any awards although it produced flowers for most of the year the flowers were small and the plant appeared to be reverting to Ann Franklin from which it sported.’

AGM Facts

• Plants of all kinds can be considered for the AGM, including fruit and vegetables.
• The list currently includes more than 7,500 plants
• New awards are made each year to keep the award list as up to date as possible.
• Failure to get an award should not prevent anyone from attempting to grow the plant. You may be able to teach the committee a thing or two.
• Reviews are conducted by  plant committees on a rolling review.
• Plants excluded from consideration are non native Orchids and those that fail the criteria.