Plant trials have been an intrinsic part of the RHS since its foundation. They bring together top British horticulturists (professional gardeners, nurserymen and plantsmen), to plan and assess groups of plants for garden decoration or use.
RHS botanists, entomologists, pathologists and horticulturists are all involved in determining the correct details, cultivation and advice for each group of plants.
Each trial results in recommendations of the best cultivars for the Award of Garden Merit (AGM) and a report with photographs, details and findings.
Many trials take place at RHS Garden Wisley but some trials and demonstrations can be seen at other locations
First International Trials Conference:
Assessment of Ornamental Plants
5 – 7 July 2011
This is the first time that a worldwide conference with a focus on the testing of ornamental plants has been undertaken. This is the opportunity for breeding companies and organisations granting awards to plants to come together to discuss approaches to plant assessment.
Find out more about the Conference
Online pea trial
We are running a trial of mangetout and sugar snap peas and we want you to take part too. By growing some of the cultivars at home and reporting on your results you will help us by providing information on how well the cultivars grow in a domestic situation.
Find out more about the online pea trial
Trials Blog
Find out about the trials, trials team and new plants.
View the blog
Trials in 2009
A list of trials and a monthly guide to what's looking best.
View the trials list
Open Days
Throughout the year we have a series of Trials Open Days.
Details of the Open Days (10KB Adobe Acrobat pdf)
2008 Results
Results and reports from last year's trials
Details of the results
Trials since 2001
Find out about recent AGM plants and reports.
View the previous trials
Trials Database
Search for details of all previous RHS trials.
View the trials database
AGM & Award Plants
What is the Award of Garden Merit and how does it identify the best plants for your garden?
Find out more
Trials Bulletins
View, download or find out how to order one of the RHS Plant Trials Bulletins.
Full list of bulletins
RHS Herbarium
Trials are an important source of material for the RHS Herbarium located at Wisley.
View the Wisley Herbarium
RHS Horticultural Database
Trials also provide an important spur for RHS research into cultivated plants and their names, use this database to search a comprehensive index of garden plant names.
View the RHS Horticultural Database