cultivars of kniphofia
Post on 08-Apr-2017
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In this chapter I focus on cultivars, including named selections of species that have been in cultivation in the last 20 years. While around 1,000 cultivars of Kniphofia have been named over the years (see Checklist of epithets, pp354417, for a complete list), only a small proportion of these are in cultivation today. The starting point for the cultivars in this chapter is those that have appeared in the RHS Plant Finder, which gives a good overview of cultivars available in the UK and Europe. To this I have added some of the more significant cultivars that have appeared beyond Europe, particularly in North America. I also hope that the information I have provided on early and widely misidentified cultivars will help correct some of the wrong attribution of their names.
RaiseR and intRoduceRFor each entry I have tried to give an indication of by whom and when the cultivar was introduced, by citing a name and date. The names given are mostly for the person who raised, or nursery that introduced, the plant. In some cases, where information is lacking, it is simply the author of its first published mention.
The sequence of introduction can be complicated, often with different individuals being involved in the initial cross, selection, licensing and introduction. It has not been practical to cite every individual involved in bringing a cultivar into existence. Therefore I have cited what I deem to be the most significant agency, whether nursery or individual.
In the Checklist (pp354417) I have tried to give more detailed information, such as full names of persons and nursery locations. In some cases I will have overlooked, or not been aware of, some people whose great efforts have been credited to someone else, for which I apologise.
date The dates attributed to the cultivar are the earliest confirmed date for the cultivar being in existence. The circumstance of the date will vary between the cultivars, depending upon the information available. For example, it might be the date it was hybridised, the date it was first listed in a nursery catalogue or other publication, or the date that a patent or plant breeders rights was applied for. The period between date of hybridising and date of availability to the public can be as much as 10 years.
A selection of Kniphofia cultivars from the 200709 RHS trial. Photographed in mid July, it shows the diverse range of colours available at that time of year
top row, left to right'Ample Dwarf', 'Jonathan', 'Dorset Sentry'
Middle row, left to right 'Amsterdam', 'Moonstone', 'Tawny King', 'Red Admiral', 'Apricot Sky', 'Jane Henry'
BottoM row, left to right 'Bressingham Sunbeam', 'Timothy', 'Rich Echoes', 'Firefly', 'Minister Verschuur', 'Safranvogel', 'Royal Standard'
At the Dell Garden in Bressingham Gardens, Norfolk, Kniphofia Elvira makes a vibrant patch of colour. This is one of the longest flowering cultivars because the flowers lack stamens and are sterile
FloweRing peRiodThe flowering period given is for when individual flowers on the spikes are open. Some cultivars are one-hit wonders; they produce a magnificent display with all the flowers opening within a short space of time, but it is all over in a couple of weeks. Kniphofia Atlanta is a great example of this, heralding the start of the poker flowering season in early June but then becoming a disappointing rosette of leaves for the rest of the year. Many newer cultivars have been raised to try and overcome this short season but there will often still be a peak, or possibly more than one peak, with only the odd spike appearing in between.
Pinpointing flowering time is further complicated by plants often starting with just a few flowers open on their spikes, so they will take a week or so before they start to look good. The larger, taller spikes will also carry on opening flowers long after they look their best. So, although the given flowering period may indicate that the plant is still in flower in November, it probably was going past its best in October. Brackets are used to indicate extremes of flowering times when these are known.
Cultivars that flower very early or late in the season may be highly dependent on frost; the buds may start to form but if frosted they will abort and there may be no flowers that year at all. Some of the winter-flowering cultivars are only suitable for frost-free zones, so although they might survive in colder climates they will rarely flower in frost-prone areas.
colouR gRoupingI have attempted to group the cultivars together by colour to help with identification or selection for garden use. In a genus where colour variation is almost continuous this is naturally going to be subjective. For example, placing an orange-red cultivar in the orange-flowered or red-flowered section is somewhat subjective. Therefore, the table (pp298301) should be used to find a cultivar if it does not appear under the expected colour section. Colour reference codes (e.g. 154C) are derived from the RHS Colour Chart.
Seed strains and series, which all contain cultivars of different colours, are included under Mixed colours at the end. However, the individual cultivars within each series can be found under the relevant colour section.
Series are convenient marketing tools to group together similar cultivars. Usually the cultivars involved will have originated from the same breeding programme, but this does not have to be the case. A series name can just be a recognised stamp of quality from a particular breeder, and any suitable cultivar could be included within that series. Their usefulness in classification is limited, as cultivars within a series can vary quite significantly in their attributes and garden worthiness.
I have described the four series that I am aware of as they contain cultivars that are frequently encountered in nurseries and catalogues and they represent significant breeding programmes.
dimensionsFor each cultivar I have given dimensions where possible. These are taken from published descriptions, RHS trial records, and my own measurements. Since not all published descriptions give all the dimensions, this information is missing in some cases, and I have certainly not seen every cultivar in this chapter. H = Height in cmS = Size of flowerhead (length diameter) in cmL = Length of flower (corolla) in mmF = Flowering period (1 = January, 12 = December)Brackets are used to indicate extremes of a range.
otheR chaRacteRisticsSome cultivars have particularly narrow leaves, less than 1cm wide, and I have termed these grass-leaved in the descriptions and table. This character is favoured by some gardeners because the foliage is often neater.
Cultivars with the RHS Award of Garden Merit (AGM) are indicated in the table and descriptions, with hardiness rating. The AGM is given to plants considered excellent for ordinary use in appropriate conditions. Kniphofias with the AGM were revised in the 200709 RHS trial (Whitehouse 2010) and the award is currently held by 23 cultivars and two species (K. northiae and K. rooperi).
cultivars 299298 cultivars
Colour of Kniphofia cultivars, including AGM and whether grass-leaved agm & hardiness rating grass-leaved
ada uniform orange
alcazar uniform red or orange-red
amazing Fun orange or red, and white or cream
ample dwarf Yellow and white
amsterdam uniform red or orange-red
apple court pink and white
apricot souffle orange or red, and white or cream
apricot uniform orange
apricots and cream orange or red, and white or cream
atlanta (tuckii group) orange or red, and white or cream
Banana popsicle (popsicle series) uniform yellow
Barbie Red or orange, and yellow
Barton Fever h6 Brownish orange and white
Bees gold uniform yellow
Bees Flame uniform red or orange-red
Bees Jubilee uniform orange
Bees lemon green and yellow
Bees sunset h5 uniform orange
Bicolor orange or red, and white or cream
Bitter chocolate Brownish orange and white
Bobs choice uniform yellow
Border Ballet mixed colours, seed-raised cultivars
Bressingham comet Red or orange, and yellow
Bressingham gleam uniform orange
Bressingham sunbeam uniform orange
Brimstone Bloom h5 green and yellow
Bronze torch uniform yellow
Buttercup h5 uniform yellow
c.m. prichard uniform yellow
candlelight uniform yellow
caroles crush uniform red or orange-red
catherines orange uniform orange
K. caulescens coral Breakers orange or red, and white or cream
K. caulescens John may Red or orange, and yellow
K. caulescens oxford Blue Red or orange, and yellow
chichi uniform red or orange-red
cobra Brownish orange and white
coolknip Yellow and white
coral Flame h5 uniform red or orange-red
coral sceptre uniform pink to pinkish orange
creamsicle (popsicle series) uniform orange
dawn sunkiss pink and white
dawn pink and white
grass-leaved cultivaragm colour
dingaan uniform yellow
dorset sentry uniform yellow
drummore apricot uniform orange
early Buttercup uniform yellow
echo duo (echo series) Brownish orange and white
echo mango (echo series) uniform orange
echo Rojo (echo series) uniform red or orange-red
elvira uniform orange
Ember Glow (tneg) (glow series) uniform orange
erecta uniform red or orange-red
ernest mitchell uniform yellow
False maid uniform yellow
Feuerkerze Red or orange, and yellow
Fiery Fred h6 uniform orange
Firefly uniform orang