• AGM plants

    AGM plants have been through a rigorous trial and assessment programme. They are:

    • Excellent for ordinary use in appropriate conditions
    • Available to buy
    • Of good constitution
    • Essentially stable in form & colour
    • Reasonably resistant to pests & diseases

Planning new trials

Each year the main RHS committees agree a list of exciting new trials to replace those which have come to an end 

Hydrangea 'Miss Saori'At this point, the trials planning cycle gains momentum to find the forum members to assess these trials. Each forum is made up of 10 plant specialists and eminent horticulturists, so when recently I held the first meeting of the new Hydrangea macrophylla trial, the forum included the National Collection holders plus the Dutch author of the Encyclopedia of Hydrangeas and other renowned horticulturists in the industry.
We are running this trial not at RHS Garden Wisley but at both Savill Gardens, part of the Crown Estate, and Abbotsbury Subtropical Garden in Dorset, to better see the effect of soil pH on these plants.
Part of my role as the trial officer is to help facilitate the trial, so in autumn of 2013 we took around 800 softwood cuttings to grow on the wish list of cultivars for the trial, and collected more mature plants which included the 2014 Chelsea Plant of the Year - Hydrangea macrophylla ‘Miss Saori’ (see photo, above).

Assessing the Stipa trialOne of the great treats as a trials officer is the opportunity to visit the sites where trials are being undertaken. So as part of the hydrangea trial work, I visited both Savill Gardens (a first time for me) and also Abbotsbury, which is among one of my personal favourites.

I was also able to drop into Knoll Gardens on my way home, a four acre garden and nursery in Dorset and have a catch up with the owner Neil Lucas, one of of the UK’s leading ornamental grass specialists. Knoll Gardens are one of the sources who supplied plant material for another one of our current trials - Stipa and other Stipeae, which is in its second year here at Wisley.

More from the RHS

See a list of current RHS Plant Trials (235kB pdf)

Find out more about the Award of Garden Merit

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