Dr Liz Beal

Liz leads our research programme into Phytophthora and also leads the team answering pathology enquiries received by RHS Gardening Advice

What do you do?

My research focuses on improving our knowledge and advice on common diseases affecting UK gardens with a focus on Phytophthora. Day-to-day tasks involve conducting molecular work, analysing data, writing scientific papers and setting up lab or field experiments.
When I am not working on my research projects I’m most likely in the lab examining diseased plant specimens to help answer member’s plant health enquiries.

The aim of our research is to feed into the advice we provide, giving more information about diseases and pests important to UK gardeners.

Why is your team’s research important?

The number of enquiries that the Pathology team answers is steadily increasing each year. This makes it ever more important to deal with members’ questions efficiently. I lead the team overseeing prompt answers for our members and contributing to publishing information about any new diseases we find.

One of the most important diseases to gardeners is Phytophthora root rot. Our research aims to provide better answers by improving the knowledge and advice we give on managing this disease in gardens.

Projects I’m working on now

  • Management of Phytophthora in gardens
  • Powdery mildews ‘Right plant, right place’

Completed projects

  • Susceptibility of garden plants to Phytophthora root rot
  • Susceptibility of garden plants to Armillaria
  •  Behaviour of severed rhizomorphs of Armillaria mellea and A. gallica in growing media
  • The action of allicin (garlic extract) against Armillaria


I am proud to have represented the RHS at several international conferences. Meeting other scientists from around the world, developing my knowledge and understanding of plant pathogens, and giving updates about current RHS research are all big accomplishments for me.

Participating in national and local TV and radio shows – raising the profile of plant pathologists in the UK while increasing the public’s knowledge about fungi and other plant diseases is also something I am extremely proud of.
I am also an editor for the journal New Disease Reports.


  • Beal EJ, Waghorn IAG, Perry JN, Clover GRG, Cromey MG. (2020) Susceptibility of garden plants to Phytophthora root rot. Plant Disease (in press)
  • Cromey M, Drakulic J, Beal E, Waghorn I, Perry J, Clover G. (2020) Susceptibility of garden trees and shrubs to Armillaria root rot. Plant Disease, 104, pp483-92
  • Newbery F, Robinson RJ, Beal E, Scrace J. (2020). First record of Septoria rudbeckiae on Rudbeckia in the United Kingdom. New Disease Reports 42, 2
  • Thines M, Denton G, Beal E, Kilty A, Denton J, Shin H-D, Choi Y-J. (2019) Peronospora aquilegicola sp. nov., the downy mildew affecting columbines in the UK is an invasive species from East Asia. European Journal of Plant Pathology
  • Newbery F, Beal E, Scrace J. (2019) First record of Alternaria thunbergiae on Thunbergia alata in Europe. New Disease Reports, 39, p14
  • Beal E, Waghorn I, Scrace J, Henricot B. (2018) First report of Phytophthora tentaculata affecting Santolina in the UK. New Disease Reports, 37, p8
  • Drakulic J, Gorton C, Pérez-Sierra AM, Clover G, Beal E. (2017) Associations between Armillaria species and host plants in UK gardens. Plant Disease, 101, pp1903–09
  • Denton G, Beal E, Kilty A, Denton J, Choi Y-J, Thines M. (2015) Characterisation and risk assessment of the emerging Peronospora disease on Aquilegia. Mycological Progress, 14, p69
  • Beal E, Henricot B, Peace A, Waghorn I, Denton J. (2015) The action of allicin against Armillaria spp. in vitro. Forest Pathology, 45, 6, pp450–58

PhD Students

  • Supervisor to Rosie Latham who is studying for a MRes on ‘Determining the main risks to native and cultivated Vaccinium spp. in the UK’ (start date postponed until Feb/ March 2021 due to Covid-19 restrictions). This MRes project is a collaboration between the University of Warwick, NIAB EMR and the RHS

Get involved

The Royal Horticultural Society is the UK’s leading gardening charity. We aim to enrich everyone’s life through plants, and make the UK a greener and more beautiful place.