RHS Plant Trials and Awards

RHS Plant Trials allow for multiple selections of the same plant to be grown side by side for comparison. The best may receive a prestigious RHS Award of Garden Merit (AGM). The plants may be grown from seed or vegetative material, and are submitted by nurseries, individuals and breeders.

We trial a wide range of ornamental and edible garden plants and houseplants, including existing cultivars and species of plants, and brand-new introductions, to test their health, performance and weather resistance. This is to help home gardeners pick the best plants that have all-round value.

The trials are assessed by a judging panel made up of experts in that group of plants, who use the trial results to inform their decision to grant plants the RHS Award of Garden Merit (AGM) status. Each assessment is then ratified by the relevant RHS Plant Committee.

Visitors to RHS Wisley can view ongoing plant trials in the Trials Garden. Trials can also be seen in the dedicated beds at RHS Hyde Hall, RHS Rosemoor and in The Old Frameyard at RHS Bridgewater. Individual trials are regularly held at RHS Harlow Carr and sometimes take place at other gardens and nurseries across the UK.