• 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)

  • Crocosmia – 2019–20
  • Persicaria (bistort / knotweed) – 2019–20
  • Echinacea (coneflower) – 2016–20
  • Paeonia (peony) – 2016–20
  • Sanguisorba (burnet) – 2017–20
  • Nepeta (catmint) – 2017–20
  • Fritillaria imperialis*  – 2019–20
  • Lagerstroemia (crepe myrtle) – 2017–21
  • Physocarpus (ninebark) – 2014–20
  • Hibiscus – 2015–19
  • Viburnum – 2013–20
  • Dwarf French beans – 2019
  • Florence fennel – 2019
  • Ridge cucumbers – 2019
  • Spring sown bulb onion – 2019
  • Rosmarinus (rosemary) – 2016–2019
  • Blueberry – 2018–20
  • Raspberry – 2018–20
  • Cypripedium (lady's slipper orchid) – 2016–20
  • Eucomis (pineapple lily) – 2017–20
  • Lilium (lily) – 2018–20
  • Apiaceae – 2019–20
*To be planted in autumn 2019


Download a plan of the Trials Field (4.7MB pdf)


People's Choice demonstration displays*

  • Clematis (Harlow Carr)

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


Off-site trials

  • Erica (heather) 2015–20 – Threave Garden and Estate
  • Cornus (dogwood) 2017–20 – RHS Garden Hyde Hall
  • Iris reticulata (bulbous iris)2017–20 – RHS Garden Hyde Hall
  • Gentiana (gentian) – 2016–19 – Holehird Gardens
  • Hemerocallis (daylily) – 2018–21 – Sissinghurst and Floors Castle
  • Geum – 2019–21 – RHS Garden Harlow Carr
  • Spirea - 2019–22 - East Ruston Old Vicarage

AGM assessment by Roundtable

  • Restio 
  • Astrantia
  • Liatris
  • Ornamental apple
  • Aconitum

Return to RHS plant trials main page

Trials results for gardeners



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