Award of Garden Merit

The Award of Garden Merit, or AGM, is an award made to garden plants by the British Royal Horticultural Society after a period of assessment by the appropriate committees of the Society. Awards are made annually after plant trials (which may last for one or more years, depending on the type of plant being trialled) at RHS Garden Wisley and other RHS gardens, or after observation of plants in specialist collections, and are intended to judge the plants' performance for conditions in the UK. Trial reports are made available as booklets and on the RHS website. The awards are reviewed periodically in case plants have become unavailable or have been superseded by more recent, superior cultivars.
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