Dahlia

Final Trials Report

2011

Trials Office The Royal Horticultural Society Garden, Wisley, Woking, Surrey, GU23 6QB

Final Report for Trial No. 1894 – Dahlia 2011 1

RHS Trial of Dahlia

Introduction to Dahlia There are 30 species of Dahlia and they originate from Central and South America. The flowers look wonderful in mixed borders in late summer and autumn and make stunning cut flowers. The shorter cultivars also make excellent patio container plants. The dahlia is a very accommodating plant that will grow well in most types of soil. The plants perform best in full sun and prefer moist but well-drained soil. They also benefit from organic matter and a general fertiliser being added to the soil. Deadheading encourages a succession of flowers through the season. Objectives The objectives of the trial were:

To assess plants for the Award of Garden Merit

To assess, compare and demonstrate a range of cultivars, in the open ground, submitted by professional and amateur growers.

Judging Members of the Dahlia Trials Assessment Panel inspected the trial at Wisley on the 11th & 23rd August; 8th & 22nd September and 11th October. The Trials Assessment Panel considered the plants using the following criteria:

Continuous flowering (5 points)

Disease resistance (5 points)

Earliness (5 points)

Quality of bloom (5 points)

Vigour (5 points)

Foliage (5 points)

Trial assessment 11 October 2011

Final Report for Trial No. 1894 – Dahlia 2011 2

Entries

There were 62 cultivars planted in the open ground, and 25 entries in patio containers in this trial of dahlias. New entries were submitted as rooted cuttings and other entries were propagated from tubers retained from the 2010 trial. Entries were submitted by breeders, nurseries and individuals in the UK and Europe.

Cultivation The following fertilisers were applied on 25th May 2011 in accordance with the RHS Soil Scientist's recommendations and in preparation for planting: • Ammonium sulphate (for nitrogen) at 40g/m2 (1.5oz/yd2) • Sulphate of potash (for potassium)at 30g/m2 (1.2oz/yd2) • No additional fertiliser was required for magnesium or phosphorus. The pH of the soil was considered a little high at 7.3, but sulphur chips were not used. The trial was planted on: • 7th June 2011 into the open ground • 3rd June into patio containers which were put out onto the Trials Field on 21st June Dahlias need regular watering to obtain the best results and all of the plants had the benefit of a drip irrigation system. The entries were watered on planting and continued to be watered and fed with a liquid feed as necessary through the season. A few entries were damaged by very heavy rain and stormy weather in September and damaged stems were removed where necessary. Pest and Disease The following sprays were used on the trial when necessary: Aphox (insecticide, active ingredient pirimicarb) for Aphid and Systhane (fungicide, active ingredient myclobutanil) for Mildew. Other Findings Although no disbudding took place this year, it was noted that disbudding can often improve the flowering display with a number of the Dahlia classifications.

Plants Receiving AGMs During Trial

The following are the plants thought to fulfil the Award of Garden Merit criteria during the trial and to be worthy of receiving the award. The criteria which a plant needs to fulfil in order to receive the award are:

excellent for ordinary garden use

available

reasonably resistant to pests and diseases

of good constitution

essentially stable in form and colour

reasonably easy to grow

Final Report for Trial No. 1894 – Dahlia 2011 3

Hardiness ratings are as follows: H3 – hardy outside in some regions; needs frost-free protection in winter

Plants Awarded AGM

Dahlia 'Melody Harmony' AGM for use in containers (H3) 2011

Registered 2008, Classification: Small Decorative

Votes 7-0. [Trial no. 2 - grown in containers].

Raised by: Verwer-Dahlias B.V.

Sent to trial by: Verwer-Dahlias B.V.

Widely available.

Comments: A lovely dahlia. Nice dark foliage compliments the flowers well. Very upright. Sturdy. Good strong stems. Nice even shaped plants which have filled the pots nicely. Flowers are well supported by the foliage, not in the foliage and not too far above it. Has done well with the bad weather. Started flowering early in the season. Has flowered its heart out.

Description: Plant height 80cm. Very robust habit. Flowers 8cm long x 11cm in diameter. Outer petals Purple 75C fading to Purple 75D; darker veins on the other side of the petal, Purple 75A; inner petals a colour between Creamy White 159C-D, tipped with Purple 75A. Foliage base Dark Green 147A heavily flushed with a colour between Greyed-Purple group N187A and Brown Group 200A towards tips. Strigulose edge to leaf, glabrous elsewhere. Stems Greyed-Purple group N187A, glaucous, lightly hairy.

Dahlia HAPPY SINGLE PRINCESS 'HS Princess' AGM for use in containers (H3) 2011

Registered 2010, Classification: Single-flowered

Votes 7-0. [Trial no. 17 - grown in containers].

Raised by: Verwer-Dahlias B.V.

Sent to trial by: Verwer-Dahlias B.V.

Available.

Comments: Fabulous foliage. Flowers are held well above the foliage. Nice compact plants, more compact than some other Singles. The new green foliage is attractive.

Description: Plant height 75cm. Upright habit. Flowers 2.5cm long x 8cm in diameter. Ray florets White NN155B flushed Purplish Pink 75A especially mid to tip, stronger and more striped beneath, obvious disk scales tipped Brown 166A, unopened and open florets Yellow 14A. Foliage very dark,

Final Report for Trial No. 1894 – Dahlia 2011 4

almost black Green 147A predominately and strongly flushed 203B. Leaves glabrous except for strigulose edges; much paler beneath with veins flushed purple grey. Stems very dark Purplish Red, darker than 187A, glaucescent (very glossy beneath where rubbed off), glabrous.

Dahlia 'Knockout' AGM for use in containers (H3) 2011

Registered 2011, Classification: Single-flowered

Votes 7-0. [Trial no. 19 - grown in containers].

Raised by: K Hammett

Sent to trial by: Plantipp B.V.

Available.

Comments: A rugged plant. Stunning dark foliage. Flowers held above the foliage. Pristine flowers. Flowers have lovely dark centres. Been good all year.

Description: Plant height 73cm. Vigorous plants with upright, spreading habit. Flowers 9.8cm in diameter. Flat outer florets, Vivid Greenish Yellow (brighter than 2A). Fine lines of red purple on the reverse of the outer florets giving the appearance of Grayish Red (closest to 176A) veining from the front. Disc dark Red-black 187A, opening Strong Orange (N163A-N163B) with Vivid Orange-yellow (closest to 23A). Calyxes darker than Grayish Red 176A. Leaves divided and almost black. Stout stems, dark Red-black (closest to 187A) and oval in cross section.

Final Report for Trial No. 1894 – Dahlia 2011 5

Dahlia HAPPY SINGLE FLAME 'HS Flame' AGM for use in containers (H3) 2011 Registered 2007, Classification: Single-flowered

Votes 7-0. [Trial no. 21 - grown in containers].

Raised by: Verwer-Dahlias B.V.

Sent to trial by: Young Plants Ltd

Available.

Comments: A really outstanding Dahlia. A star plant. Fantastic dark foliage. Flowers are held well above the foliage. Fantastic fiery flower colour. Lots of flowers. Flowers don't fade much. Compact habit. Hard to fault. You can't better the foliage and flower colour.

Description: Plant height 85cm. Upright to spreading habit. Flowers 4cm long x 8cm in diameter. Outer petals Yellow 3A at base changing to Red 545A at tips. Very dark foliage, base Dark Green overflushed with Black 203B. Leaf features: strigulose edge to leaf, glabrous elsewhere. Stems Greyed Purple 187A, glaucescent.

Dahlia 'Josie Gott' AGM (H3) 2011

Registered 2007, Classification: Small Ball

Votes 7-0. [Trial no. 28 - grown in the open ground].

Raised by: K Stock

Sent to trial by: K Stock

Available.

Comments: Has been particularly good. Nice foliage from top to bottom. Good overall height. Nice strong stems. Beautiful flower colour and shading. Lovely purplish tinge right the way down the flower. Flowers have good form – petals bend right back to the stem. Flowered for a long time.

Description: Plant height 178cm. Vigorous plants, erect habit. Flowers 9.5cm in diameter. Flowers white, flushed lilac/light purple (N80C-75B) in centre and to a lesser degree at petals apices, base brilliant greenish yellow (1B). Stems strong yellow green (144A) flecked darker green (143A). Leaves moderate olive yellowish green (greener and yellower than 137A-138A). Green foliage. Stems light green and oval in cross section.

Final Report for Trial No. 1894 – Dahlia 2011 6

Dahlia 'Susan Carey' AGM (H3) 2011

Registered 2010, Classification: Large Semi-Cactus

Votes 7-0. [Trial no. 33 - grown in the open ground].

Raised by: D McMaster

Sent to trial by: D McMaster

Freely available.

Comments: Lovely clean flower colour, not too harsh. Very bright flowers. Sensational colour. The cool green in the centre of the flowers keeps it looking cool. Shows its flowers well. Would stand out in a border. Excellent foliage. Loads or flowers, especially for such a large flowered dahlia. As good as you'll get for a large flowered dahlia. The looser / softer flower form was liked for use in the garden.

Description: Plant height 130cm. Short habit with large flowers. Flowers 5cm long x 13cm in diameter, bright, pale Yellow 1A-B. Foliage Mid Green N137A. Leaf features: strigulose edges, elsewhere glabrous. Stems green, glabrous.

Final Report for Trial No. 1894 – Dahlia 2011 7

Dahlia 'April Heather' AGM (H3) 2011

Registered 2010, Classification: Collerette

Votes 7-0. [Trial no. 48 - grown in the open ground].

Raised by: J Shaw

Sent to trial by: Halls of Heddon

Available.

Comments: Foliage compliments the flowers perfectly. Lovely blooms. Delightful blend of colours. Beautiful. Colour looks good today - lovely shades of colour in the flowers. Flowers have an even collar. Consistently well-formed flowers. Nice strong stems. Fantastic. Lots of flowers. Flowers from the base to the top of the plants. Has been consistently good through the season.

Description: Plant height 197cm. Erect habit. Flowers 13cm in diameter. Cupped outer florets. Outer florets Brilliant Greenish Yellow (1A-2A but brighter) at the base paling to Light Greenish Yellow 1C towards the tip, large areas blushed with and the occasional streak of Moderate Red (paler than 47A) changing to a blush of Purplish Red (closest to 60C) towards the tip, gives the overall effect of apricot. Inner florets (collar) white overlaid with Brilliant Greenish Yellow 1A at the base paling towards the apex. Central disc Vivid Orange Yellow 23A opening Vivid Orange Yellow (23A -21A). Green foliage. Stems light green and round in cross section.

Dahlia 'Stadt Spremberg' AGM (H3) 2011

Registered 2012, Classification: Medium Decorative

Votes 7-0. [Trial no. 55 - grown in the open ground].

Raised by: S Koschker

Sent to trial by: Deutsche Dahlien

Available.

Comments: Has the wow factor. Beautiful. Superb colour. Single eye on some flowers. Flowers die gracefully. Consistently stunning. Fabulous / amazing flower colour. Been good every time so far.

Description: Plant height 150cm. Strong flower stems; flowers above foliage Flowers 6cm long x 13cm in diameter. Outer petals Orange group N25 A; petals in the middle a colour between Orange-Red N30 A and N30 B; inner petals Orange-Red N30 B at base grading to Orange-Red N30 A in the middle and Red 44 at tips, some with occasional yellow stripes. Foliage Yellow-Green 147A. Leaves glabrous. Stems green flushed with Greyed-Purple 185B.

Final Report for Trial No. 1894 – Dahlia 2011 8

The following entries have been recommended for the AGM but cannot receive the award until they have been registered and / or are available. It is the responsibility of the sender to inform the Trials Office at Wisley that all queries have been resolved.

Dahlia 'Trelyn Crimson' AGM (H3) 2011 Subject to Availability

Registered 2011, Classification: Collerette

Votes 7-0. [Trial no. 51 - grown in the open ground].

Raised by: R Tudor

Sent to trial by: R Tudor

Comments: Excellent foliage. Very attractive dark foliage compliments the flowers. Flowers are held well above the foliage. Strong stems. Beautiful flowers. Very attractive flower colour. Outstanding. Unique flower colour with a hint of blue in the petals. Regular flowers. Has got better and better.

Description: Plant height 150cm. Robust, bushy habit. Flowers 3cm long x 11cm in diameter. Petals a bit darker than Red 46B. Foliage Yellow-Green 147A. Leaf features: strigulose edge to leaf, slightly hairy on the down side. Stems green, flushed with Greyed-Purple 185B.

Final Report for Trial No. 1894 – Dahlia 2011 9

Dahlia 'Wigo Super' AGM (H3) 2011 Subject to Availability and Registration

Classification: Small Decorative subject to confirmation on registration

Votes 7-0. [Trial no. 56 - grown in the open ground].

Raised by: W te Winkel

Sent to trial by: Deutsche Dahlien

Comments: Good, healthy foliage. Good strong stems. Nice dark bloom on the stems. Flowers are held well above the foliage. Nice bright flowers. Lovely with the golden edge to the flowers. Very floriferous with lots of buds to come. Very warm mix of colours. Terrific colour with good form. Flowers age well. A good garden plant. Has stood up well to the bad weather. A typical border Dahlia, would look beautiful with heleniums or chrysanthemums. Superb plant.

Description: Plant height 130cm. Habit upright and strong, looking vibrantly floriferous habit. Flowers 6cm long x 8cm in diameter. Outer petals Yellow 5C flushed Orange 30D over flushed darker Orange 30A in middle band leaving base and tips yellow, inner petals stronger Orange N30B with slightly more orange tint to the yellow tips. Foliage mid Green N137A. Leaf features: glabrous except for strigulose edges, sublustrous. Stems green flushed with Greyed Brown N199A, glaucescent, glabrous.

Dahlia 'Crystal Beauty' AGM (H3) 2011 Subject to Registration

Classification: Small Waterlily subject to confirmation on registration

Votes 7-0. [Trial no. 64 - grown in the open ground].

Raised by: Geerlings

Sent to trial by: Geerlings

Available.

Comments: Has looked consistently good over the last few years and flowered for a long period. A useful tall plant. Good strong stems. Lots of flowers. Super flower colour. Stunning. Spectacular. Nice distribution of colour. Also useful as a cut flower.

Description: Plant height 190cm. Robust, upright habit. Flowers 6cm long x 11cm in diameter. Very base of petals yellow; outer and inner petals white flushed with Purple 76A on young flowers and Purple 77C on mature ones. Petals in the middle of the flower completely white. Foliage a bit darker than Yellow-Green 147A. Leaf features: strigulose edge to leaf, lightly hairy on the back and minutely on the front side. Stems green.

Final Report for Trial No. 1894 – Dahlia 2011 10

Trial Index and Senders Details

Planting number

Cultivar and sender Raiser Awards

Container Plants

1 'Melody Gipsy' Verwer-Dahlias B.V.

Verwer-Dahlias B.V.

2 'Melody Harmony' Verwer-Dahlias B.V.

Verwer-Dahlias B.V.

3 'Maya' Verwer-Dahlias B.V.

Verwer-Dahlias B.V.

4 'Spanish Jewel' K Stock

K Stock

5 'Yellow Tom' Halls of Heddon

Unknown

6 'Valerie McDonald' K Stock

K Stock

7 'Benito' Green Works Int B.V.

Green Works Int B.V.

8 'Gallery Rivera' Verwer-Dahlias B.V.

Verwer-Dahlias B.V.

9 'Rojo Paramo' Green Works Int B.V.

Green Works Int B.V.

10 'Ruby Murray' K Stock

K Stock

11 'Ace Summer Emotions' Verwer-Dahlias B.V.

Verwer-Dahlias B.V.

12 'Veracruz' Green Works Int B.V.

Green Works Int B.V.

13 'Clarion' New World Plants Ltd

K Hammett

14 'Petite Harvest' J R Gott

J R Gott

Final Report for Trial No. 1894 – Dahlia 2011 11

Planting number

Cultivar and sender Raiser Awards

15

'Star Wars'

Star Wars 'VDTG14' (Dark

Angel Series) Verwer-Dahlias B.V.

Verwer-Dahlias B.V.

16 'My-nute Blend' The Late Mr D Walker

D Walker

17 Happy Single Princess 'HS

Princess' Verwer-Dahlias B.V.

Verwer-Dahlias B.V.

18 'Golden Margaret' Geerlings

Maarse

19 'Knockout' Plantipp B.V.

K Hammett

20 'Brighteyes Pathfinder' J R Gott

J R Gott

21 Happy Single Flame 'HS

Flame' Young Plants Ltd

Verwer-Dahlias B.V.

22 'Shadow Play' Halls of Heddon

K Hammett

23 Happy Single Party 'HS Party'

Young Plants Ltd Verwer-Dahlias B.V.

24 'Lilianna W' J R Gott

M Wilczynski

25 Candy Eyes ('Zone Ten')

John Woods Nurseries K Hammett

Plants in the open ground Planting number

Cultivar and sender Raiser Awards

2 Anemone flowered

26 'Floorinoor' Deutsche Dahlien

L Verhoeven

7 Pompon

27

'Moor Place' ROGUE PLANTS named 'April Heather' Halls of Heddon

Newnham J Shaw

6A Small Ball

28 'Josie Gott' K Stock

K Stock

29 'Blyton Softer Gleam' L Stothard

L Stothard AGM (H3) 2010

30 'Blyton Royal Velvet' L Stothard

L Stothard

6B Miniature Ball

31 'Casper' K Stock

K Stock

32 'Pembroke Levenna' Halls of Heddon

A G Davies

Final Report for Trial No. 1894 – Dahlia 2011 12

Planting number

Cultivar and sender Raiser Awards

9B Large Semi-Cactus

33 'Susan Carey' D McMaster

D McMaster

34 'Hapet Fantastic‟ Deutsche Dahlien

P Haslhofer

9C Medium Semi-Cactus

35 'Hillcrest Jessica J' Cruickshanks

L Jackson

36 'Oakwood Fire' S Silver

S Silver

37 'Hillcrest Candy' F Taylor

L Jackson

9D Small Semi-Cactus

38 'Oakwood Goldcrest' S Silver

S Silver

39 'Rockliffe Billy' T E Thompson

T E Thompson

40 'Delphine' V Wakefield

Unknown

41 'Jessica' Geerlings

Hale

42 'Oakwood Firelight' S Silver

S Silver

43 'Parkland Rave' J Wheatley

Rowse

44 'Hapet Ideal' G Carey

P Haslhofer

11 Fimbriated

45 'Ella Mae' R Knight

R Knight

3 Collerette

46 'Suzanne' S Clensy

S Clensy

47 'Abacus Sol' Abacus Nurseries

D Hill

48 'April Heather' Halls of Heddon

J Shaw

49 'Carstone Firebox' Halls of Heddon

J Kidd

50 'Olivia' J R Gott

I Kitchener

51 „Trelyn Grand Slam' 'Trelyn Crimson' R Tudor

R Tudor

52 'Fontmell Kaz' J R Gott

K Stock

53 'Lilian Alice' Halls of Heddon

G Chambers

5C Medium Decorative

Final Report for Trial No. 1894 – Dahlia 2011 13

Planting number

Cultivar and sender Raiser Awards

54 Seedling Ko212 Deutsche Dahlien

S Koschker

55 'Stadt Spremberg' Deutsche Dahlien

S Koschker

5D Small Decorative

56 'Wigo Super' Deutsche Dahlien

W te Winkel

57 'Karma Prospero' Verwer-Dahlias B.V.

Verwer-Dahlias B.V.

5E Miniature Decorative

58 'Oakwood Dazzle' S Silver

S Silver

59 „Erna Panzer‟ Deutsche Dahlien

H Panzer

60 'Tiptoe' Halls of Heddon

T Cleghorn

4 Waterlily

61 'Rancho' G Carey

E Turc

62 'Edwin's Sunset' F Taylor

B Woodford

63 'Kilburn Rose' G Hill

G Hill

64 'Crystal Beauty‟ Geerlings

Geerlings

65 'Sandia Melody' Geerlings

Birch Bay Dahlias

66 'Olivia Mari' F Taylor

B Woodford

67 'Ken's Rarity' V Wakefield

Farquar

68 'Blue Wish' R & L Evans

Unknown Duijzer

10 Miscellaneous

69 'Tally Ho Double' Bridgemere Nurseries INTEREST ONLY

Bridgemere Nurseries

70 'Honor Francis' O Mason

Unknown

71 'Waltzing Mathilda‟ Rose Cottage Plants

Ru-Ro Plant

1 Single flowered

72 'Miss Alison' RBG Kew

A M G Smith

73 'Magenta Star' J Wheatley K Hammett AGM (H3) 2008

74 'Twyning's Revel' J Wheatley

M Twyning

Single Orchid

Final Report for Trial No. 1894 – Dahlia 2011 14

Planting number

Cultivar and sender Raiser Awards

75 'Trelyn Seren‟ R Tudor

R G Tudor

Double Orchid

76 'Maiko Girl' K Stock

K Stock

Dark Red Flowers

77

'Nuit d'Été' (sometimes incorrectly called 'Summer Night') Aylett Nurseries

Unknown

78 'Pat Knight' R Knight

I Kitchener

79 'Sam Hopkins' Geerlings

C Geerlings

80 'Arabian Night' (syn. 'Arabian Knight') World's End Garden Nursery

Weijers

81 Arabian Night' (syn. 'Arabian Knight') Wisley Plant Centre

Weijers

82 'Arabian Night' (syn. 'Arabian Knight') V Wakefield

Weijers

83 'Karma Naomi' Verwer-Dahlias B.V.

Verwer-Dahlias B.V.

84 'Karma Choc' Verwer-Dahlias B.V.

Verwer-Dahlias B.V.

85 'La Recoleta' 'Rip City' Rose Cottage Plants

Nuland

86 'Barbarry Sultan' B Davies

B Davies

87

Cosmos x Dahlia 'Mexican Black' INTEREST ONLY Cotswold Garden Flowers

Unknown

N.B Names that are struck through have been checked by RHS Botanists / corrected during the trial. Sender Details Abacus Nurseries, Drummau Road, Skewen, Neath. SA10 6NW Aylett Nurseries Ltd, North Orbital Road, St Albans, Herts, AL2 1DH Bridgemere Nurseries, Bridgemere, Nr. Nantwich, Cheshire, CW5 7QB Mr G Carey, c/o Trials Office Mr S Clensy, 26 Maplewood, Skelmersdale, Lancashire, WN8 6RJ Cotswold Garden Flowers, Sands Lane, Badsey, Worcestershire, WR11 7EZ. Ms I Cruickshanks, Ridgeview Nursery, Crossroads by Longridge, West Lothian, EH47 9AB Mr B Davies, 29 Laithes Crescent, Smithies, Barnsley, S71 3AE

Deutsche Dalien, Fuschsien und Gladlolen, Gelsellschaft, Maasstra e 153, 47608 Geldern Walbeck, Germany

Final Report for Trial No. 1894 – Dahlia 2011 15

Messrs R & L Evans, 3 Pentwyn Gowerton Road, Three Crosses, Swansea, SA4 3QH Mr C Geerlings, Geerlings Dahlias, Kadijk 38, 2104AA Heemstede, Netherlands Mr J R Gott, 22 Summerville Road, Milnthorpe, Cumbria, LA7 7DF Green Works International B.V., Witte Paal 341, 1741 LE Schagen, Holland, The Netherlands Halls of Heddon, West Heddon Nursery, Heddon-on-the-Wall, Northumberland, NE15 0JS Mr G Hill, Coach House, Church Farm, Kilburn, York, YO61 4AH John Woods Nurseries, Main Road, Pettistree, Woodbridge, Suffolk, IP13 0HH Mr R Knight, Bogga Mill, Lanreath, Looe, Cornwall, PL13 2PA Mrs O Mason, Dial Park, Chaddesley Corbett, Kidderminster, Worcs, DY10 4QB Dr D McMaster, 20 Cabra Road, Hillsborough, Co Down, BT26 6NB New World Plants Ltd, Court Farm, Mansell Gamage, Herefordshire, HR4 7LE Plantipp BV, Brunel 21, 3401 LJ IJsselstein, Netherlands Ms L Hart, Hardy Display, RBG Kew, Richmond, Surrey, TW9 3AB Rose Cottage Plants, Bay Tree Farm, Epping Green, Essex, CM16 6PU Mr S Silver, 'Oakwood', 29 Thornhill, Chacombe, Banbury, Oxfordshire, OX17 2JG Mr K E Stock, c/o Trials Office. Plants from this sender are available from Gilberts Nursery, Dandysford Lane, Sherfieldenglish, Romsey, Hampshire, S051 6DT Mr L Stothard, 88A High Street, Blyton, Gainsborough, Lincolnshire, DN21 3LA Mr F B Taylor, Taylor's Dahlias, 12 Shawbury Grove, Sale, Cheshire M33 4DF Mr T E Thompson, 4 Cae Coch Cottage, Kielsterton Road, Flint, CH6 5SJ Mr R Tudor, 34 Victoria Road, Fleur de lys, Blackwood, Gwent NP12 3UG The Late Mr D Walker c/o Trials Office Mr J Wheatley, Stonebarn, Moorledge Farm, Chew Magna, Bristol, Avon BS40 8TL Verwer-Dahlias B.V., Fa Gebr Verwer, 3e Poellaan 73/75, 21 61 DL, Lisse, Netherlands Mrs V Wakefield, Bramdean House, Bramdean, Nr Alresford, Hampshire, SO24 0JU Wisley Plant Centre, RHS Garden Wisley, Woking, Surrey, GU23 6QB Worlds End Garden Nursery, Worlds End Nurseries, Moseley Road, Hallow, Worcester, WR2 6NJ Young Plants Ltd, Whitehill Farm, Alderminster, Stratford Upon Avon, Warwickshire, CV37 8BW Plant Trials Bulletin on Dahlias

A colour trials bulletin was published in 2009 entitled “Open-centred Dahlias and can be downloaded from the RHS website using the following link www.rhs.org.uk/Plants/RHS-Publications/Plant-bulletins/Open-centred-Dahlias

Alternatively if you would like a printed copy please contact: The Trials Office, RHS Garden Wisley, Woking, Surrey GU23 6QB. Please enclose an A4 SAE. They cost £2 per copy (a donation towards costs); cheques to be made out to Royal Horticultural Society.

Final Report for Trial No. 1894 – Dahlia 2011 16

Dahlia Classifications Text Source: Nineteenth Supplement to The Tentative Classified List and International Register of Dahlia Names 1969 (2007). Photographs: RHS Trials

D. 'Moonfire'

Group 1: Single–flowered dahlias

Single outer ring of florets, which may overlap, the centre forming a disc.

D. 'Ryecroft Marge'

Group 2: Anemone–flowered dahlias

One or more outer rings of generally flattened ray florets surrounding a dense group of tubular florets, which are longer than the disc florets in Single dahlias, and showing no disc.

D. 'Don Hill'

Group 3: Collerette dahlias

A single outer ring of generally flat ray florets, which may overlap, with a ring of small florets (the collar), the centre forming a disc.

D. 'Charlie Dimmock'

Group 4: Waterlily dahlias

Fully double blooms characterised by broad and generally sparse ray florets, which are straight or slightly involute along their length giving the flower a shallow appearance. The depth should be less than half the diameter of the bloom.

D. 'Dikara Midnight'

Group 5: Decorative dahlias

Fully double blooms showing no disc. The ray florets are generally broad and flat, or slightly twisted and usually bluntly pointed, and may be involute for no more than 75% of their length.

Final Report for Trial No. 1894 – Dahlia 2011 17

D. 'Blyton Softer Gleam'

Group 6: Ball dahlias

Fully double blooms, ball shaped or slightly flattened. The ray florets are blunt or rounded at the tips, spirally arranged, with margins involute for at least 75% of the length of the florets.

D. 'Will's Ringwood Rosie'

Group 7: Pompon dahlias

Fully double, spherical blooms of miniature size, not exceeding 50mm in diameter, with florets involute for the whole of their length.

D. 'Lakeland Sunset'

Group 8: Cactus dahlias

Fully double blooms, the ray florets are usually pointed, the majority narrow and revolute for 50% or more of their length and either straight or incurving.

D. 'Julie's Delight'

Group 9: Semi-Cactus dahlias

Fully double blooms, the ray florets are usually pointed, and revolute for more than 25% of their length and less than 50% of their length (longitudinal axis), broad at base and either straight or incurving.

D. 'Bishop of Llandaff'

Group 10: Miscellaneous dahlias

Any dahlias which do not fall into one of the listed groups e.g. Peony-flowered dahlias.

Final Report for Trial No. 1894 – Dahlia 2011 18

D. 'Anna Cozens'

Group 11: Fimbriated dahlias

Ray florets should be evenly split or notched into two or more divisions, uniformly throughout the bloom creating a fringed effect. The petals may be flat, involute, revolute, straight, incurving or twisted.

D. 'Juul's Allstar'

Group 12: Single-Orchid dahlias

Single outer ring of florets surrounding the disc. Ray florets are uniformly either involute or revolute.

D. 'Mayan Pearl'

Group 13: Double-Orchid dahlias

Fully double blooms, showing no disc. Ray florets are narrowly lanceolate and either involute or revolute.

Lilliput dahlias

A low-growing type of dahlia usually no more than 30cm in height having single, semi-double or double florets attaining 2.6cm or so in diameter. Especially suitable for borders or display in containers on patios.

Dwarf bedding dahlias

The use of “Dw.B” after the classification of a cultivar indicates that these are dwarf bedding dahlias, not usually exceeding 60cm in height.

Source: Horticultural Trials and Relations, RHS Garden Wisley, Woking, Surrey GU23 6QB

E-mail: trials@rhs.org.uk

More information about RHS Trials and other colour illustrated reports can be found on the RHS Website: http://www.rhs.org.uk/trials