Chilli peppers trial results 2023
Objectives and purpose of the trial
What is an RHS Award of Garden Merit?
The RHS Award of Garden Merit (AGM) is intended to help gardeners choose plants that are likely to perform well, and is only awarded to plants that are:
- Excellent for ordinary use in appropriate conditions
- Available
- Good constitution
- Essentially stable in form and colour
- Reasonably resistant to pests and diseases
Judging criteria
The following factors were all taken into consideration as part of the judging of the trial:
- Plant habit
- Fruit abundance and uniformity
- Fruit skin quality
- Disease resistance
Chilli pepper AGM winners
This successful cross-site trial involved a wide variety of chili peppers grown at three RHS Gardens. The cultivars that received AGMs demonstrated strong performance across all trial locations, showcasing healthy plants with good growth habits and a high yield of quality fruit. Additionally, they experienced minimal issues with pests and diseases. As a result of the trial, three new cultivars were granted an AGM, four cultivars had their AGM reconfirmed, and two cultivars had their AGMs rescinded. The list of AGMs now reflects the current availability of the best chillies to grow.
Capsicum annuum (Longum Group) 'Fuego'
chilli pepper 'Fuego'
- 0.1–0.5 metres
- 0.1–0.5 metres
Capsicum annuum (Longum Group) 'Fuego'
chilli pepper 'Fuego'
- 0.1–0.5 metres
- 0.1–0.5 metres
Why the AGM was awarded
AGMs rescinded
Plants and location
What was planted?
Where was it planted?
The trial took place at three sites: RHS Bridgewater, Greater Manchester and RHS Rosemoor, Devon in unheated poly-tunnels and RHS Wisley, Surrey in an unheated glasshouse. Seeds of each trial entry were initially sown in early February 2023 in heated propagation areas. Here are some considerations for sowing and planting out the chilli peppers:
- By growing chillies, you can enjoy a range of colours, shapes, flavours and levels of heat
- As tender plants, chillies are best grown in a greenhouse, however, they can also be grown outdoors in a sunny spot, in pots or in the ground
- These plants generally like similar growing conditions to tomatoes
- Sow seeds indoors from late winter to mid-spring – chillies generally need a long growing season, and an early start will give you an earlier and longer harvest
- Chilli seeds need warmth to germinate – around 21°C (70°F) so use a warm windowsill or heated propagator
Cultivation
Planting process
How plant health was managed
Challenges
Biological controls were used to manage pests such as aphids, glasshouse whitefly, two-spotted spider mites and thrips during the trial. Caterpillars were removed by hand.
Watering and maintenance
The plants were watered by hand (and at RHS Wisley by drip irrigation in the later stages), with high potassium fertiliser applied. As the plants grew, taller entries were staked to prevent them from bending or breaking. As part of the trial, plants were harvested at regular intervals, with one plant of each entry left unharvested.How to grow chilli peppers
Explore all the information you need to know to grow and care for chilli peppers in your garden
Who was involved?
Judges of the trial
The chilli pepper trial was assessed by the Vegetable Trial Assessment Forums at RHS Bridgewater (26 July and 30 August 2023), RHS Rosemoor (16 August and 6 September 2023) and RHS Wisley (8 August and 31 August 2023). Across the three chilli pepper forums, the members brought expertise and experience in the following areas: Vegetable growing, showing and judging, plant nurseries and retail, horticultural journalism and RHS Fruit, Vegetable and Herb Committee (FV&H) members.
The chilli pepper judges included: Barry Newman (RHS Wisley Forum Chair and RHS FV&H Committee Member), Ian Clemens (RHS Rosemoor Forum Chair and RHS FV&H Committee Member), John Constable (Formerly with Elsom Seeds and Allium Seeds), Keith Hine (National Vegetable Society Judge), Richard White (Former Trial Garden Manager, Tozer Seeds), Britta Horsthemke (Estate Gardener), Duncan Palmer (Vegetable grower), Jon Wheatley (Horticulturist, designer, RHS Shows and Britain in Bloom), David Allison (RHS Bridgewater Forum Chair and RHS FV&H Committee Member), Mark Fletcher (Head of Agronomy, National Institute of Agricultural Botany), Joe Lofthouse (Team Leader Edibles at RHS Harlow Carr), James Oakey (Buying Director, Hayloft Plants), Roy Roberts (Senior plant breeder of vegetables, MRL Seeds Ltd), Sue Stickland (Writer on vegetable growing and Director of Wales Seed Hub) and David Thornton (Exhibition grower and National Vegetable Society Secretary).
Suppliers to the trial
List of plants in the trial
Handy tools and information
- Full article - Filter for AGM plants and refine by colour, height and season of interest
Find an AGM plant online
Filter for AGM plants and refine by colour, height and season of interest - Full article - Explore advice and helpful tips from our resident experts
Gardening advice
Explore advice and helpful tips from our resident experts - Full article - Check how hardy plants are using the RHS hardiness ratings system
Hardiness ratings
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RHS Grow app
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Get in touch
For more information on our RHS Plant Trials or to access older trial reports, please get in touch with our team via email at [email protected].
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