• 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
Aerial view of trials field at Wisley

Portsmouth Field (RHS Garden Wisley)

  • Agapanthus (African lily) – 2014-18
  • Persicaria (bistort / knotweed) – 2018-21*
  • Echinacea (coneflower) – 2016-20
  • Paeonia (peony) – 2016-20
  • Sanguisorba (burnet) – 2017-20
  • Nepeta (catmint) – 2017-20
  • Petunia – 2018
  • Lagerstroemia (crepe myrtle) – 2017-21
  • Physocarpus (ninebark) – 2014-19
  • Hibiscus – 2015-19
  • Viburnum – 2013-20
  • Onion – 2018
  • Cabbage – 2018
  • Aubergine – 2018
  • Cauliflower – 2018
  • Winter cabbage – 2018
  • Rosmarinus (rosemary) – 2016-2019
  • Blueberry – 2018-19
  • Raspberry – 2018-19
  • Cypripedium (lady's slipper orchid) – 2016-19
  • Eucomis (pineapple lily) – 2017-19
  • Lilium (lily) – 2018-19
 

*to be planted in autumn 2018

Download a plan of the Trials Field
 


People's Choice demonstration displays*

  • Tagetes (marigolds)
  • Latest bedding varieties


*These will be voted for by visitors to RHS Garden Wisley, and are not part of the AGM trials programme


 

Off-site trials

  • Erica (heather) 2015-19 – North / South Forums: Threave Garden and Estate / John Hall Plant Nursery
  • Hypericum (St John's wort) – 2015-18 – Sir Harold Hillier Gardens
  • Cornus (dogwood) 2017-20 – RHS Garden Hyde Hall
  • Iris reticulata (bulbous iris)2017-20 – RHS Garden Hyde Hall
  • Chrysanthemum – 2017-19 – RHS Garden Harlow Carr
  • Gentiana (gentian) – 2016-19 – Holehird Gardens
  • Hemerocallis (daylily) – 2018-21 – Sissinghurst and Floors Castle
  • Hydrangea macrophylla (shrubby hydrangea) – 2015-19 – The Savill Garden & Abbotsbury
  • Sarracenia (pitcher plants) – 2016-18 – Hampshire Carnivorous Plants
  • Geum – 2019-21 – RHS Garden Harlow Carr (already in situ but not assessed until 2019)
  • Winter cabbage – 2018 – RHS Garden Rosemoor
  • Shallot – 2018 – RHS Garden Rosemoor

AGM assessment by Roundtable

  • Epimedium (barrenwort)
  • Brugmansia (angel's trumpet, datura)
  • Deciduous Euonymus, Nyssa and Fothergilla
  • Betula (birch)
  • Hosta
  • Symphyotrichum (aster)
     

►Return to RHS plant trials main page

►Trials results for gardeners



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