Hemerocallis trial results 2020–2023

Objectives and purpose of the trial

The idea of an updated Hemerocallis (daylily) trial, the last being in 1977, came about after the RHS Herbaceous Committee saw a 2013 demonstration by the British Hosta and Hemerocallis Society at Great Dixter Garden. This 2020–2023 RHS Plant Trial aimed to assess, compare and redefine which plants were worthy of the RHS Award of Garden Merit (AGM) in the current climate and weather conditions. The trial included a range of long-standing well-known cultivars and existing award-winning plants, alongside a selection of commercially new cultivars.
Hemerocallis trial in the Walled Garden at Floors Castle July 2021
Rows of colourful Hemerocallis at Floors Castle August 2023

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:

  • Complete plant: Garden value and beauty; vigour and good rate of growth, hardiness and resistance to pest and disease
  • Foliage: Clean, healthy, appealing, in proportion to scapes and flowers
  • Scape: Height and strength, in relation to flowers and foliage; branching and bud count

  • Flower: Substance and weather resistance and colour(s) and pattern
  • Distinctiveness: In flower, performance, season of bloom, scent, rebloom, unusual beauty, other special plant features

Hemerocallis AGM winners

This successful cross-site trial involved duplicate plantings, which demonstrated cultivars were consistent in performance at both trial locations. It also showcased healthy plants with good growth habits and excellent blooms. The trial judges were able to grant eight new AGMs, reconfirm 12 AGMs, and 34 cultivars had their AGMs rescinded. The list of AGMs now reflects the current availability of the best Hemerocallis cultivars to grow.

Hemerocallis are tough and easy to grow. They will grow on most soils, are low maintenance, and don’t need staking. Who has time for staking these days?

Kirsty Wilson, Trial Judge and Head of Gardens at Balmoral Castle

Why the AGM was awarded

New AGM winners with forum comments and hardiness ratings

Hemerocallis ‘Berlin Tallboy’ AGM (H6) 2024

  • Forum comment: Big distinct yellow flowers, many tall thick scapes, held upright, healthy foliage and fills space well, tolerates a dry location, foliage clean and healthy
  • Average height and size: Scape up to 140cm, bloom up to 15cm
  • Flowering time: Midseason, June to July

Hemerocallis ‘El Desperado’ AGM (H6) 2024

  • Forum comment: Attractive clean lemon yellow flowers with burgundy chevron, foliage has a glaucous look – eye catching, dramatic flower, good broad healthy foliage upright plants, compact habit
  • Average height and size: Scape up to 80cm, bloom up to 12cm
  • Flowering time: Late season, July to August

Hemerocallis ‘Corky’ AGM (H6) 2024

  • Forum comment: Many scapes, fine upright foliage, floriferous, flowers are delicate and distinctive,  
    early flowerer, dark scapes, small compact plant, and outstanding look
  • Average height and size: Scape up to 75cm, bloom up to 8cm
  • Flowering time: Midseason, June to July

Hemerocallis ‘Dan Mahony’ AGM (H6) 2024

  • Forum comment: Individual flower petals have rippled edged, mottled colour of flower petal - known as ‘cheetah spot’, all strong plants, buds are attractive with two tones, foliage glaucous blue colour, consistent look, strong plants
  • Average height and size: Scape up to 80cm, bloom up to 11cm
  • Flowering time: Early to midseason, May to June

Hemerocallis ‘Golden Prize’ AGM (H6) 2024

  • Forum comment: Upright foliage, foliage with blue hue, attractive crimp edge to yellow/gold flowers, flowers attractive large petals, held and presents well, scape good strong and healthy
  • Average height and size: Scape up to 70cm, bloom up to 16cm
  • Flowering time: Late season, July to August

Hemerocallis ‘Green Flutter’ AGM (H6) 2024

  • Forum comment: Attractive and distinct, yellow flowers with distinct green throat, ruffled petals, attractive individual flowers, clumps of upright healthy dark green foliage
  • Average height and size: Scape up to 70cm, bloom up to 10cm
  • Flowering time: Late season with rebloom, July to August

Hemerocallis ‘Marion Vaughn’ AGM (H6) 2024

  • Forum comment: Upward held elegant attractive scented flowers, held on tall airy scapes, nice foliage with a twist to leaf, plant in proportion, good upright foliage. Ticks all the boxes
  • Average height and size: Scape up to 100cm, bloom up to 12cm
  • Flowering time: Midseason, June to July

Hemerocallis ‘Sasseness’ AGM (H6) 2024

  • Forum comment: Attractive distinct magenta colour, striking crimp edge to large flowers, good clean and healthy upright foliage
  • Average height and size: Scape up to 60cm, bloom up to 20cm
  • Flowering time: Mid to late season, June to August
Reconfirmed AGMs with forum comments and hardiness ratings

Hemerocallis ‘All American Chief’ AGM (H6) 2012

  • Average height and size: Scape up to 81cm, bloom up to 23cm
  • Flowering time: Early to midseason with rebloom, May to July

Hemerocallis ‘Arctic Snow’ AGM (H6) 2012

  • Average height and size: Scape up to 58cm, bloom up to 14cm
  • Flowering time: Midseason, June to July

Hemerocallis ‘Beauty to Behold’ AGM (H6) 2012

  • Average height and size: Scape up to 61cm, bloom up to 14cm
  • Flowering time: Mid eason, June to July

Hemerocallis ‘Burning Daylight’ AGM (H6) 1993

  • Average height and size: Scape up to 71cm, bloom up to 15cm
  • Flowering time: Midseason, June to July

Hemerocallis citrina AGM (H6) 2012

  • Average height and size: Scape up to 114cm, bloom up to 13cm
  • Flowering time: Mid to late season, June to August

Hemerocallis ‘Condilla’ AGM (H6) 2012

  • Average height and size: Scape up to 51cm, bloom up to 11cm
  • Flowering time: Early to midseason, May to July

Hemerocallis ‘Custard Candy’ AGM (H6) 2012

  • Average height and size: Scape up to 61cm, bloom up to 11cm
  • Flowering time: Early to midseason with rebloom, May to July

Hemerocallis ‘Fooled Me’ AGM (H6) 2012

  • Average height and size: Scape up to 61cm, bloom up to 14cm
  • Flowering time: Early to midseason with rebloom, May to July

Hemerocallis ‘Pink Damask’ AGM (H6) 1993

  • Average height and size: Scape up to 91cm, bloom up to 9cm
  • Flowering time: Midseason with rebloom, June to July

Hemerocallis ‘Red Precious’ AGM (H6) 1993

  • Average height and size: Scape up to 56cm, bloom up to 9cm
  • Flowering time: Mid to late season, June to August

Hemerocallis ‘Spider Man’ AGM (H6) 2012

  • Average height and size: Scape up to 61cm, bloom up to 11.5cm
  • Flowering time: Early to midseason with rebloom, May to July

Hemerocallis ‘Stafford’ AGM (H6) 2012

  • Average height and size: Scape up to 71cm, bloom up to 15cm
  • Flowering time: Midseason, June to July
Early look at Hemerocallis trial in new trial area at Sissinghurst
Close up of Hemerocallis citrina on display as part of the trial

AGMs rescinded

These selections were found to no longer be worthy of the AGM, and they will be removed from the AGM list. The forum recommended to rescind the RHS Award of Garden Merit from the following entries:
AGMs rescinded with forum comments

Hemerocallis ‘Always Afternoon’

  • Forum comment: Muddy colour of flower poor, not distinct, poor foliage

Hemerocallis ‘Asterisk’

  • Forum comment: Poor growth, not enough flower or buds, weak all over, disappointing

Hemerocallis ‘Cherry Eyed Pumpkin’

  • Forum comment: Cluster of old and new flowers messy with old dead held too long, scapes grouped so looks gappy from distance, scruffy foliage

Hemerocallis ‘Curly Cinnamon Windmill’

  • Forum comment: Small plants, few scapes and few flowers

Hemerocallis ‘Eggplant Escapade’

  • Forum comment: Plants not consistent, foliage floppy, lack flowers and petal colour tips end in muddy brown colour not attractive

Hemerocallis ‘Elegant Candy’

  • Forum comment: Poor foliage with floppy habit

Hemerocallis ‘Jellyfish Jealousy’

  • Forum comment: Unusual spider form, lovely but no overall plant impact and shows weather damage

Hemerocallis ‘Lady Neva’

  • Forum comment: Habit weak, floppy, attractive distinct flower, few thin and whippy scapes and poor bud count

Hemerocallis ‘Mary’s Gold’

  • Forum comment: Shorter scape and foliage. Not consistent flower spread across plants

Hemerocallis ‘Moonlit Masquerade’

  • Forum comment: Foliage is poor and streaky. Flowers grey and brown held too long. Can see dead flower and pods, messy and disappointing

Hemerocallis ‘Old Tangiers’

  • Forum comment: Old flowers held too long so clash with new, plus scape in foliage

Hemerocallis ‘Primal Scream’

  • Forum comment: Flowers in foliage, and only one clump with enough flower

Hemerocallis ‘Russian Rhapsody’

  • Forum comment: Not enough flower in proportion to foliage

Hemerocallis ‘Selma Longlegs’

  • Forum comment: Not enough flower in proportion and scape count low

Hemerocallis ‘Serena Sunburst’

  • Forum comment: Scapes in foliage, which is dry and unhealthy

Hemerocallis ‘Sir Modred’

  • Forum comment: Flower with velvet look, rain damaged, with flower in floppy foliage

Hemerocallis ‘Strawberry Candy’

  • Forum comment: Small flower size, dwarf habit with no distinct flower colour combination

These existing AGMs, which were not in the trial due to not having availability at the time the trial took place, are also to be rescinded:

  • Hemerocallis ‘August Frost’
  • Hemerocallis ‘Cat Dancer’
  • Hemerocallis ‘Cayenne’
  • Hemerocallis ‘Grey Witch’
  • Hemerocallis ‘Holly Dancer’
  • Hemerocallis ‘Jamaican Me Crazy’
  • Hemerocallis ‘Julie Newmar’
  • Hemerocallis ‘Karen’s Curls’
  • Hemerocallis ‘Killer’
  • Hemerocallis ‘Lime Frost’
  • Hemerocallis ‘Mahogany Magic’
  • Hemerocallis ‘North Wind Dancer’
  • Hemerocallis ‘Performance Anxiety’
  • Hemerocallis ‘Radiant Moonbeam’
  • Hemerocallis ‘Ruby Spider’
  • Hemerocallis ‘Running Late’
  • Hemerocallis ‘Tuxedo Junction’

Plants and location

What was planted?

This trial included 121 trial entries made up of the existing Hemerocallis AGM plant list, which in 2017 had 91 cultivars on it. Some plants were chosen by the RHS Herbaceous Committee. Some plants selected for the trial had previously been rescinded by the RHS and a few extras were added for interest. Entries were submitted by nurseries in the UK Trade.

Where it was planted?

This was a dual trial at two RHS Partner Garden sites – the Walled Garden at Floors Castle Walled Garden, Kelso, Scotland, with the kind permissions of the Duke and Duchess of Roxburghe and at the National Trust (NT) Sissinghurst Castle Garden, Kent. The trial was planted out in October 2018. Here are some considerations for planting out the Hemerocallis:

  • Hemerocallis prefer well-drained, fertile soil but are adaptable and can tolerate poorer soils
  • Plants prefer some moisture in spring and summer but dislike waterlogged soil
  • Hemerocallis perform best in full sun but can also thrive in partial shade

  • Richer-colored varieties may become bleached in scorching sun. Also avoid heavy shade as it leads to straggly growth and poor flowering
  • Hemerocallis are fully hardy and do not require winter protection
  • Most Hemerocallis are deciduous, losing their leaves in autumn, though some evergreen types retain their leaves year-round

Did you know?

There is a British Hosta and Hemerocallis Society? Learn more >

Cultivation

Planting process

Three plants of each entries were supplied as bareroot plants, which were collected and planted at the Gardens of Floors Castle Walled Garden and at NT Sissinghurst Castle Garden during October 2018, with additions added until September 2019 at both sites.
 
The Floors Castle Garden site used a bed prepared within the Walled garden, with each cultivar displayed using a triangle-grouping format along the west wall. Of the 52 entries displayed, five cultivars were only supplied and grown here.

Sissinghurst Castle Garden created a new enclosed trial area alongside their Vegetable garden where the same triangle grouping was used. Of the 69 entries displayed, only 13 cultivars were supplied and grown here.

How plant health was managed

Weather

During the Hemerocallis trial, plants looking to gain the RHS Award of Garden Merit (AGM) experienced extremes of weather in the flowering season including heatwave temperatures and torrential rain, and performed well without protection or special care in both Scotland and Sussex.

Challenges

To prevent the transfer of the Hemerocallis gall midge, which overwinters in the soil and can significantly reduce flowering displays, all plant entries were supplied with the soil completely removed. As an ongoing measure, the team looked out for key symptoms including distorted flowers and buds that failed to open.

Who was involved?

Judges of the trial

The Hemerocallis Trials Assessment Forum were split into two groups North and South and viewed the trial on each site up to four times per year. Members were encouraged to visit the replica site at least once each year as part of the assessment, however due to Covid-19 restrictions in 2020, no visits were possible.

The Hemerocallis judges included: Jim Marshall (Chair, Sissinghurst and RHS Herbaceous Committee member), Gavin McNaughton (Chair, Floors, Macplants Nursery and RHS Alpine Committee member), Sarah Cook (RHS Herbaceous Committee member), Andrew Simmons (Retired Head Gardener of Floors Castle), Kirsty Wilson (Head of Gardens, Balmoral Castle), Dr Paula Dyason (Strictly Daylilies Nursery), David Moorsom (Specialist grower), Jim Gardiner (RHS Vice President), Paul Harris (Brookfield Plants), Lady Rosemary Fitzgerald (Beggars Roost Plants), Bob Brown (Cotswold Garden Flowers) and Andrew McSeveney (RHS Plant Trial Officer).

Suppliers to the trial

List of plants in the trial

View all the Hemerocallis trialled at RHS Wisley
  • Hemerocallis ‘All American Chief’
  • Hemerocallis ‘Always Afternoon’  
  • Hemerocallis ‘Arctic Snow’   
  • Hemerocallis ‘Asterisk’   
  • Hemerocallis ‘Beauty to Behold’   
  • Hemerocallis ‘Ben Bachman’   
  • Hemerocallis ‘Berlin Tallboy’   
  • Hemerocallis ‘Black Arrowhead’   
  • Hemerocallis ‘Burning Daylight’   
  • Hemerocallis ‘Buzz Bomb’   
  • Hemerocallis ‘Carolina Cool Down’   
  • Hemerocallis ‘Cartwheels’   
  • Hemerocallis ‘Cherry Eyed Pumpkin’   
  • Hemerocallis ‘Chesapeake Crablegs’   
  • Hemerocallis ‘Citrina’   
  • Hemerocallis ‘Condilla’ (d)  
  • Hemerocallis ‘Corky’   
  • Hemerocallis ‘Curly Cinnamon Windmill’   
  • Hemerocallis ‘Custard Candy’   
  • Hemerocallis ‘Dan Mahony’   
  • Hemerocallis ‘Double River Wye’   
  • Hemerocallis ‘Eggplant Escapade’   
  • Hemerocallis ‘El Desperado’  
  • Hemerocallis ‘Elegant Candy’   
  • Hemerocallis ‘Elizabeth Salter’   
  • Hemerocallis ‘Fooled Me’   
  • Hemerocallis ‘Frans Hals’   
  • Hemerocallis ‘Fried Green Tomatoes’   
  • Hemerocallis ‘Golden Chimes’   
  • Hemerocallis ‘Golden Prize’   
  • Hemerocallis ‘Golden Zebra’   
  • Hemerocallis ‘Green Flutter’   
  • Hemerocallis ‘Heavenly Flight of Angels’   
  • Hemerocallis ‘Henry D. Allnutt’  
  • Hemerocallis ‘Humdinger’   
  • Hemerocallis ‘James Marsh’   
  • Hemerocallis ‘Janice Brown’   
  • Hemerocallis ‘Jellyfish Jealousy’   
  • Hemerocallis ‘Lady Neva’   
  • Hemerocallis ‘Laughing Giraffe’   
  • Hemerocallis lilioasphodelus (syn. Hemerocallis flava)  
  • Hemerocallis ‘Marion Vaughn’   
  • Hemerocallis ‘Mariska’   
  • Hemerocallis ‘Mary’s Gold’   
  • Hemerocallis ‘Minnie Wildfire’   
  • Hemerocallis ‘Moonlit Masquerade’   
  • Hemerocallis ‘Old Tangiers’   
  • Hemerocallis ‘Oy Vey’   
  • Hemerocallis ‘Pink Damask’   
  • Hemerocallis ‘Primal Scream’   
  • Hemerocallis ‘Red Precious’   
  • Hemerocallis ‘Russian Rhapsody’   
  • Hemerocallis ‘Sammy Russell’   
  • Hemerocallis ‘Sasseness’   
  • Hemerocallis ‘Selma Longlegs’   
  • Hemerocallis ‘Serena Sunburst’   
  • Hemerocallis ‘Sir Modred’  
  • Hemerocallis ‘Spider Man’  
  • Hemerocallis ‘Stafford’   
  • Hemerocallis ‘Strawberry Candy’   
  • Hemerocallis ‘Unzip slip’   
  • Hemerocallis ‘Webster’s Pink Wonder’   
  • Hemerocallis ‘Whichford’   
  • Hemerocallis ‘Yellow Angel’
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