Tulipa (tulip), Single Late, Viridiflora and Darwin Hybrids trial results 2026
Objectives and purpose of the trial
A tapestry of tulips brings the Trials Garden to life in May 2026
Hundreds of vibrant tulips on display in the RHS Wisley trial beds
What is an RHS Recommended: Award of Garden Merit?
The RHS Recommended: Award of Garden Merit is intended to help gardeners choose reliable plants and is only awarded to plants that are:
- Healthy, with good overall growth and appearance
- Excellent performers, resilient in the right conditions
- Available to buy in garden centres or online
- Reasonably resistant to common pests and diseases
- True to type, keeping a consistent colour and form
Judging criteria
The following factors were all taken into consideration as part of the judging of the trial:
- Overall appearance – including proportions, uniformity, sturdiness and foliage quality
- Flower impact – colour, consistency and performance as blooms age
- Weather and pest resistance
- Length of flowering period
Tulipa – RHS Recommended: AGM winners
Single Lates, as you might expect from their name, are the showstoppers at the end of the tulip flowering season. They’re fantastic value for money and give a dazzling show in the garden.
Why the RHS Recommended: AGM was awarded
Tulips of every colour, shape and form create a spectacular display
Tulip judges explore the trial entries at RHS Wisley in April 2026
RHS Recommended: AGMs rescinded
Plants and location
What was planted?
This trial included 100 entries (including some duplicates) across four tulip groups: 38 Darwin Hybrid, 33 Single Late, 17 Viridiflora and 12 multi-stemmed cultivars. The bulbs were supplied by UK bulb specialists working with growers and exporters in the Netherlands.
Each group offered different qualities for gardeners:
- Darwin Hybrid tulips are known for their large, goblet-shaped flowers and sturdy stems. Reliable and weather-resistant, they are among the best tulips for creating bold spring displays and often return well for several years
- Single Late tulips produce elegant, egg-shaped flowers on tall stems towards the end of the tulip season. Their height and wide range of colours make them ideal for adding impact to borders and cutting gardens
- Viridiflora tulips are recognised by their distinctive green-flamed petals, which remain visible as the flowers mature. Long flowering and full of character, they bring unusual colour and texture to spring planting schemes
- Multi-stemmed tulips divide into mini-bouquets of three to four flowers
Throughout the trial, the RHS Trials team recorded key data and photographed each entry to assess how well the cultivars perform for gardeners today. Assessments included bulb size, flowering period, flower colour, form and uniformity, vigour, sturdiness and overall garden performance. Herbarium specimens were taken from cultivars recommended for the RHS Recommended: AGM.
Where was it planted?
The tulip bulbs were planted in the open ground across four trial beds in the Trials Garden at RHS Wisley, creating the foundations for a showstopping spring showcase. Here are some considerations for planting out tulips:
- The best time to plant tulips is in November, but if you’ve bought them earlier, it is better to get them in the ground than store them for a long time
- Pick a sunny, free-draining site in the garden
- Alternatively, plant them in containers in peat-free compost that drains well
- Remember to water them during the growing season
- Different tulip divisions flower at different times. With careful selection, you can have a succession of tulips from early to late spring
Cultivation
Planting process
Each of the 100 trial entries included 50 bulbs. The bulbs were planted in five rows of 10, with cultivars arranged alphabetically within each group: Darwin Hybrid, Single Late, Viridiflora and multi-headed tulips.
Bulbs were planted in blocks of shallow trenches measuring 10cm deep, 50cm wide and 100cm long. Entries were spaced 60cm apart, with two rows running across the width of each bed. A layer of horticultural grit was added to the base of each trench to improve drainage.
After planting, the beds were mulched with strulch, a straw-based mulch used to help suppress weeds. A low, solar-powered electric fence was installed around the trial area to deter badgers, while deadheading was kept to a minimum during the growing season.
How plant health was managed
Challenges
Pest and disease issues were limited throughout the trial. One entry, Tulipa ‘Sorbet’, showed signs of stunted growth and premature foliage dieback in mid-April. The RHS Plant Health team found evidence of Penicillium (a fungus) infection within the bulb. This fungus can enter through damaged bulbs and cause rot and dieback.
As Penicillium does not persist for long in the soil and posed little risk of spreading to neighbouring entries, the affected bulbs remained in the trial. Despite the infection, Tulipa ‘Sorbet’ went on to perform well.
Seasonal conditions
Weather throughout the 2025–2026 season provided a useful test of the trial entries. A cold spell in December 2025 was followed by a mild winter, while January and February 2026 were wetter than average. Warm conditions in March 2026 encouraged growth and, by the first judging session on 1 April 2026, the Darwin Hybrid tulips had begun to flower. Strong winds in mid-April provided a further test of plant vigour and stem strength across the trial.
How to grow tulips
Explore all the information you need to know to grow and care for tulips in your garden
Discoveries
Multi-headed tulips make their RHS trial debut | April to May 2026
Appearing in an RHS tulip trial for the first time, 12 multi-stemmed cultivars, including Tulipa ‘Purple Elegance’, impressed by producing multiple flowers per bulb and helped to extend the display period.
Trial stars win public vote | April 2026
Visitors to RHS Wisley voted for their favourite tulips in the RHS People's Choice Award poll. Tulipa ‘Flaming Memory’ and Tulipa ‘Blushing Lady’ received the most votes and were also among the trial’s standout performers.
Single Late tulips stand firm in strong winds | Mid-April 2026
Strong winds provided a valuable test of stem strength. Cultivars such as Tulipa ‘Flaming Memory’ and Tulipa ‘Blushing Lady’ performed particularly well, maintaining their form and flowering for around three weeks.
Viridiflora tulips stood out in the trial | Mid-April 2026
The 17 Viridiflora cultivars, like Tulipa ‘Virichic’, delivered strong visual impact despite being smaller in number than the Darwin Hybrid and Single Late groups. Their distinctive green-flushed petals provided a contrast to more traditional tulip forms, reinforcing their value as both unusual and reliable garden plants.
Warm weather brings a spectacular display | April 2026
An unusually warm spell saw temperatures rise into the mid-20s, helping the tulip beds reach a vibrant peak and attracting large numbers of visitors to RHS Wisley.
Darwin Hybrids begin to flower | April 2026
The first judging session coincided with the opening blooms of the 38 Darwin Hybrid cultivars, marking the start of the trial display.
Who was involved?
Judges of the trial
The 2026 Tulipa judges included: Adam Taylor (Co-Chair and Director, Taylors Bulbs), Richard Wilford (Trial Co-Chair, garden designer and author), John Amand (Director, Jacques Amand International), Camilla Bassett-Smith (television presenter and writer), Teresa Clements (former Chair of the RHS Bulb Expert Group), Fergus Garrett (Head Gardener, Great Dixter), Pollyanna Wilkinson (garden designer), Clare Brown (owner, Plant Passion), Lucy Bellamy (journalist and author), Polly Nicholson (National Collection holder) and Eloise Bedwell (RHS horticulturist).
Suppliers to the trial
List of plants in the trial
Adam Taylor’s favourite tulips from the trial
Tulipa 'Light and Dreamy' (4)
tulip 'Light and Dreamy'
- 0.1–0.5 metres
- 0–0.1 metre
Tulipa 'Blushing Lady' (5)
tulip 'Blushing Lady'
- 0.5–1 metres
- 0.1–0.5 metres
Tulipa 'Light and Dreamy' (4)
tulip 'Light and Dreamy'
- 0.1–0.5 metres
- 0–0.1 metre
Tulipa 'Blushing Lady' (5)
tulip 'Blushing Lady'
- 0.5–1 metres
- 0.1–0.5 metres
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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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