Named by Linnaeus in 1735 in honour of the Jesuit priest and naturalist Georg Josef Kamel, Camellia is a genus originating mainly from China but with a range covering a large area of South East Asia. The exact number of species is not clear but it is somewhere around 100. Camellia is an important commercial genus because of one species, Camellia sinensis, the plant from which tea is made.
Most gardeners recognise two main groups of camellias, the autumn flowering and the spring flowering. However, it is not quite that simple. Whenever a genus of many species (such as
Rhododendron, Rosa or Camellia) is used to produce a multitude of hybrids distinct groups tend to form.
There are four main camellia groups: Japonica, Reticulata, Sasanqua and Hybrid, with a number of smaller groups based around less common species, such as Camellia hiemalis, and inter-specific hybrids, such as Camellia × williamsii (Camellia japonica × Camellia saluensis).
It's a commonly held belief among gardeners that Sansanquas are the autumn flowering camellias while the rest are spring flowerers. That's not really true, certainly the Sasanquas are usually the first to bloom but with careful selection and siting it is possible to have more or less continuous flowering from early autumn to late spring.
Cultivation
Camellias are often associated with rhododendrons and azaleas and, while not that closely related, they certainly prefer similar conditions. This is not at all surprising as they come from similar climates and can often be found growing together in the wild.
Camellias are generally less tolerant of extreme cold than the hardiest rhododendrons but they are by no means fussy plants. Most species and hybrids are hardy throughout the country, needing no protection except perhaps in very cold winter areas, and the summers here are
not usually hot and dry enough to cause much damage.
To get the best out of your camellias it is important that you follow the same soil preparation methods as recommended for rhododendrons. Camellias have stronger and deeper roots but they still require the same moist, humus filled, loose, well-oxygenated topsoil if they are to thrive. Likewise regular mulching is always beneficial.
Camellias prefer a neutral to acid soil and will not tolerate the extreme acidity that most rhododendrons will. On highly acid soils the addition of small amounts of dolomite lime will not only increase the pH but will allow easier uptake of nutrients.
Once established most camellias seem to get by quite well without too much attention but they are subject to the same chlorosis problems as rhododendrons so occasional supplementary feeding is recommended. Containerised camellias should be fed regularly as they are far more subject to deficiencies due to their limited root spread.
Camellias do best in sheltered positions in light shade or where they get only morning sun. This is not so much for the plant's sake as the flowers'. The plants will tolerate exposed sunny sites but the flowers won't. Too dense shade will promote lank growth and reduce flowering. Too sunny and the flowers will burn and drop prematurely. A site that is exposed to strong winds will dramatically shorten the life of any flowers but especially camellias.
Disbudding
Many camellias set large quantities of flower buds that often result in densely crowded small bloom. Thinning out the more densely packed and weaker flower buds will produce larger blooms of better shape.
Propagation
Camellias are not always easy to propagate without specialised equipment. Seed germinates well but is of limited usefulness as it can only be used to raise new cultivars or to propagate species. Selected forms must be propagated vegetatively.
Cuttings should be taken just as the new growth is hardening off. This is usually around the end of November. Take new tip growth cuttings that are about 100-150 mm long and follow the procedures outlined in the propagation chapter. The cuttings may take several months to strike without mist or bottom heat.
Layering is very successful with camellias but frequently there are no branches close enough to ground level to layer. In such cases aerial layering is a reliable, if slow, method.
Occasionally a camellia cultivar fails to perform well on its own roots. In which case grafting onto a more vigorous stock may be necessary. Standard camellias are nearly always produced by grafting rather than simply training a standard stem.
Cleft grafting is the usual method used, however, saddle grafts and side wedges will work too. Budding is seldom used but there is no reason why it shouldn't be successful. Specialised methods, such as seed grafts, are sometimes used but these are for genuine enthusiasts that are prepared to experiment.
Pests And Diseases
Camellias are relatively disease free but you may occasionally encounter one of the following problems.
Viral diseases
These are quite common among camellias, in fact, viruses are sometimes deliberately introduced to obtain variegated flowers and foliage. The most common virus shows up as a bright yellow leaf margin. This is known as virus induced variegation. In minor cases it does little harm but it can weaken a plant by reducing the amount of available chlorophyll. Virus diseases cannot be cured, once infected the plant remains infected.
Phytophthora root rot
This disease affects many types of plants, particularly those that prefer acid woodland conditions. This fungus disease kills the plant's roots, which leads to the characteristic wilted appearance and ultimately death. Generally the symptoms are not obvious until too late. Prevention through ensuring that the soil is well drained is the best method. Plants can sometimes be saved by washing off the soil, removing the dead roots, drenching with fungicide then replanting in a well-drained position but it's seldom worth the effort.
Leaf gall
A fungal disease similar to that seen on evergreen azaleas occasionally occurs on camellias. It causes a thickening and distorting of the leaves, which is eventually become white with fungal spores. Remove any affected leaves and spray the plant with a fungicide. Do not allow affected leaves to drop near the plant.
Petal blight
This fungal disease cause the flowers to degenerate to watery mush and can damage much of the crop. Control with fungicides prior to bud break and remove any fallen petals from around infected bushes.
Die-back
This can be a serious, even fatal, problem. The foliage of young branches wilts and browns then the stem begins to die back from the tip. A canker develops that eventually ringbarks the stem causing its death. If the cankers spread to the main stems the plant may die. Treatment with fungicides will help but is not entirely successful. Overcrowding, poor drainage and poor ventilation can all contribute to this problem as well as making the spread of the disease easier.
Camellias are generally not attacked by any particularly unusual insect pests, just the run of the mill, aphids, scale, caterpillars, leaf rollers and thrips. The usual control measures are effective on camellias too.
Bagworms can cause significant damage at times. The leaf covered silken bags (see illustration) are made by the larvae and the flightless adult females of the moth Liothula omnivora. The larvae feed from within the bag, which they carry around with them for protection and camouflage. Hand picking is the simplest control, the use of insecticides is not warranted except in cases of severe infestation.
Training
Besides their normal bushy habit many camellias are suitable subjects for training. The most common forms are the standard and the espalier.
Standards can be created in two ways. The easiest is to select a young plant with a single straight stem and simply remove the lower foliage and any side shoots as they appear. Stake the main stem as it grows and once it has reached the desired height nip out the tip growth to induce the branching that will eventually form the head.
The process can be speeded up by grafting but the mechanics are not as simple. Select a vigorous upright plant that will rapidly produce the standard trunk and graft your selected cultivar onto it at the desired height. Cleft grafts are the preferred method for camellias but I have found side wedge grafts to be successful. Grafting is the only practical way to produce a weeping standard.
Espaliering is just a matter of selecting an appropriate plant and having the patience to wait long enough to see the results. There are several methods of training the branches to achieve the best coverage but most camellias with thin pliable stems (primarily Sasanquas) can be espaliered with little effort. Remember though, camellias are not natural climbers, espaliers need to be secured to the structure against which they are growing.
Other special forms.
Camellias can make effective hedges, either tightly clipped or grown informally. As might be expected of a genus that contains the tea plant camellias can withstand frequent trimming when actively growing.
Some camellias are suitable for use as ground covers but usually only while they are young. In time all but the most prostrate forms will develop into mounding bushes rather than true ground covers. Pegging the branches down as the plants grow is the only way to ensure this doesn't happen.
Camellias in containers
Camellias adapt well to container growing but they are quick to show signs of nutrient deficiencies. Nothing looks less appealing than a badly chlorotic camellia in a tiny pot. However, with regular fertilising and the right sized containers camellias will thrive and bloom heavily in pots.
As with all container plants, remember that their roots are far less insulated from the elements than those of plants in the open ground. Make sure containerised camellias get regular water in summer and in cold winter areas move the containers to sheltered positions for winter to avoid having the soil freeze solid.
Flower forms
Camellias are available in several different flower forms. The descriptions in this book are kept as simple as possible but occasionally the technical terms must be used. The terms single, semi-doubleand double are familiar and fairly self-explanatory but most of the following terms are peculiar to camellia cultivation.
Anemone
A style with large outer petals and massed small central petaloids.
Peony (paeony) and informal double
Large outer petals and smaller loosely clustered central petals and petaloids. The more fully petalled flowers are known as full peony form.
Rose form double
A double flower that opens fully to reveal the stamens, like a fully blown rose.
Formal double
This flower type has perfectly arranged concentric circles of neatly overlapping petals. Some have the petals in a very clearly defined spiral pattern.
There are also rules governing the terms used to describe the size of flowers but as most non-specialist gardeners find these to be more confusing than useful they have not been strictly adhered to.
Species and cultivars
The following selection of species and cultivars includes those most popular for garden use or that have interesting or unusual features. They are divided into hybrid groups.
Species
These are the most popular or influential of the species but they are not widely available in nurseries, most gardeners preferring the hybrids.
Camellia chrysantha (China)
A yellow camellia was a long sought after aim of plant breeders, hence the basically white cultivars with optimistic names such as 'Brushfield's Yellow'. However, in 1980 a real yellow camellia was found in the Guangxi province of China. It flowered for the first time in the West in 1984 and has since been the subject of great interest and speculation among camellia growers. It is a large species that can reach 5 m high. The large leaves are deep green and heavily veined. The bright yellow flowers are only about 60 mm diameter but it is not the size of the flowers but their potential for hybridising that initially had breeders so enthused. Reasonably hardy but prefers consistent cool to moderate temperatures, intolerant of extremes. Camellia societies have a few plants of this species but even now it is not generally available through garden centres.
Camellia forrestii (China, Vietnam)
A large shrub or small tree native with narrow elliptical leaves and small white flowers that are mildly fragrant. Early to mid season.
Camellia fraterna (China)
Grows to about 5 m high. Small elliptical leaves. 25 mm diameter white flowers with white stamens and prominent gold anthers. Slightly fragrant. Not totally hardy. Flowers mid season.
Camellia granthamiana (Hong Kong)
Very rare in the wild; known, until recently, from just one plant found in 1955. It may be a natural hybrid rather than a true species. Grows to about 3 m high. Deep green heavily veined elliptical leaves up to 200 mm long. Creamy white flowers up to 150 mm diameter with massed golden stamens. Flowers early. Not totally hardy.
Camellia hiemalis (Japan)
Not known in the wild and probably a natural hybrid between Camellia japonica and Camellia sasanqua. Grows to about 3.5 m high. 30 mm diameter pale pink flowers with golden stamens. Small to medium sized elliptical leaves. Flowers early.
Camellia kissi (North East India to Southern China)
May grow as high as 12 m but usually consideably smaller. Medium sized narrow leaves. Small white flowers that are usually fragrant. Flowers mid season to late.
Camellia lutchuensis (Southern Japan including Okinawa)
Grows to about 3 m high. Small leaves about 40 mm long. Very fragrant 50 mm diameter white flowers with white stamens and gold anthers. Not always easy to grow and not totally hardy. Flowers mid season to late.
Camellia japonica (Japan, Eastern China and Korea)
The parent of a vast number of cultivars. May grow to 15 m high in the wild. Broad deep green elliptical leaves up to 125mm long. The flower colour is variable but is usually red. Easily grown. Flowers mid season. There are several cultivated forms.
Camellia oleifera (Northern India, Southern China and South East Asia)
Grows to about 7 m high. Medium sized elliptical leaves with little or no serrations. Small white flowers with yellow stamens and slightly twisted petals. Mildly fragrant. Flowers mid season to late.
Camellia pitardii (Southern China)
Grows to about 7 m high. Medium sized heavily veined leaves up to 100 mm long. Small white, pink or white flushed pink flowers. Blooms mid season to late.
Camellia reticulata (Southern China)
Extensively used in hybridising. grows up to 15 m high in the wild. Large broad elliptical leaves with prominent veins (reticulate). 75 mm diameter mid pink flowers. Blooms mid season to late.
Camellia salicifolia (Hong Kong and Taiwan)
Grows to about 5 m high. 45 mm long narrow elliptical to oblong leaves with a very slight tomentum. Loose white flowers with white stamens. Mild fragrance. Flowers mid season to late.
Camellia saluenensis (Southern China)
Grows to about 5 m high. 45 mm long narrow elliptical leaves. 50 mm diameter white to mid pink flowers with small golden stamens. May be single or semi-double. Flowers mid season to late.
Camellia sasanqua (Japan and Ryukyu Islands)
Grows to about 5 m high. The leaves are around 55 mm long , usually narrow and distinctly pointed. 50 mm diameter white to pale pink flowers with yellow stamens. Occasionally slightly fragrant. Flowers early.
Camellia sinensis (India to China and South East Asia)
The tea plant is the most commercially important camellia. May grow to 15 m high but usually kept much smaller. Leaf size is variable; they are usually around 125 mm long but in mild moist climates they may be up to 225 mm long × 75 mm wide, heavily veined. White flowers (occasionally pale pink), about 40 mm diameter with yellow stamens. Flowers early.
Camellia transnokensis (Taiwan)
An upright bush to about 3 m high. Small bronze green leaves. Clusters of very small (25 mm diameter) white flowers with white stamens and golden anthers. Pink buds. Flowers mid season to late.
Camellia tsai (Southern China, Burma and Vietnam)
Grows to about 10 m high in the wild but usually far smaller in gardens. 90 mm long glossy bronze green elliptical leaves. Slight weeping growth habit. Clusters of small white flushed pink flowers. Mildly fragrant. Flowers mid season. Not totally hardy.
Sasanqua and Hiemalis
A group of primarily early flowering plants (autumn to late winter) that is made up of varieties and hybrids of three species; Camellia sasanqua, Camellia hiemalis and Camellia vernalis.
Akebono
Small deep green leaves. Single mid pink flowers. Excellent hedge or espalier.
Bonanza
Medium to large semi-double deep red flowers. Long flowering season. Medium sized plant, upright growth. Good in tubs.
Bonsai Baby
Small deep red double flowers. Low, somewhat spreading growth habit.
Chansonette
Large deep pink double flowers with slightly ruffled petals. A densely foliage medium sized bush. Suitable for most styles of training.
Cotton Candy
Large soft pink semi-double flowers with slightly ruffled petals. Strong growing but inclined to be rather open and benefits from regular trimming to shape.
Exquisite
Large very pale pink single flowers with ruffled and lobed petals. Long branches make it well-suited to espaliering.
Hiryu-see Kanjiro
Jennifer Susan
Soft mid pink loosely petalled semi-double flowers. Very densely foliage compact growth. Makes a good hedge or espalier.
Kanjiro
Often sold as 'Hiryu'. Deep cerise pink single to semi-double flowers with lighter coloured centre. Dark green leaves. Strong upright growth.
Mine No Yuki
Medium sized white to cream semi-double flowers with ruffled petals. Loose pendulous growth habit.
Plantation Pink
Large mid pink single flowers. Very strong growing and makes a quick hedge.
Setsugekka
Large white semi-double with ruffled, slightly incurving petals. Strong growing upright bush.
Showa No Sakae
Medium sized light to mid pink loose semi-double flowers. Distinctly weeping to horizontal growth habit. may be used in hanging baskets.
Sparkling Burgundy
Small to medium sized deep pinkish red double flowers. Long flowering season. Vigorous grower. Suitable for most training styles.
Yuletide
Small bright red single flowers with prominent golden stamens. Long flowering season. Dense compact growth. Does well in tubs.
Japonica
The species forms and hybrids of Camellia japonica are among the most popular and widely grown camellias. Also included in this group are the Higo hybrids. These often ancient forms from Japan are not widely grown in New Zealand but a few are available.
The following is a selection of some of the most popular Japonicas.
Ave Maria (1956)
Pale pink medium sized formal double. Dense compact growth. Early to mid season.
Bambino (1959)
Small coral pink anemone form with well-defined petaloid centre. Dense compact growth. Flowers mid season.
Berenice Boddy (1946)
Medium sized light pink semi-double. Vigorous grower. Flowers mid season.
Betty Sheffield Supreme (1960)
Large loose white or very pale pink double with petals edged in deep pink. A beautiful picotee effect but rather variable. A sport of 'Betty Sheffield' (1949). A vigorous, yet compact bush. Flowers mid season.
Blood of China (1928)
Medium sized deep pinkish red semi-double to peony form. Often mildly scented. Strong grower but compact. Late flowering.
Bob Hope (1972)
Large deep blackish red semi-double. Very intense flower colour and deep green leaves. Strong upright growth. Mid season to late.
Bob's Tinsie (1962)
Small deep red anemone form with a white centre. Upright, very dense and bushy. Flowers mid season.
Brushfield's Yellow (1968)
Medium sized anemone form with white outer petals and creamy yellow petaloid centre. Strong growing but densely foliaged. Flowers mid season.
C.M. Hovey (1853)
Medium sized deep red formal double. Upright growth. Late flowering.
Can Can (1961)
Medium sized light pink peony form with deep cerise pink edged petals and veins. Upright growth. Flowers mid season.
Debutante (around 1900)
Medium sized light pink full paeony form. A strong growing densely foliage bush. Leaves may be a lighter green than most camellias. One of the most widely planted camellias. Flowers mid season.
Desire (1977)
Medium sized light pink formal double with deeper coloured petal edges. Dense compact growth. Flowers mid season.
Dolly Dyer (1973)
Small bright red anemone form with a densely packed petaloid centre. A medium sized densely foliaged bush. Flowers early to mid season.
Elegans Supreme (1960)
Large deep pink anemone form with finely serrated petal edges. One of several sports of the old cultivar 'Elegans' (1831). Large wavy edged leaves. A strong growing but compact bush. Flowers early to mid season.
Grand Slam (1962)
Large deep red semi-double or anemone form. Slightly fragrant. Deep green leaves. A very strong growing upright bush. Flowers mid season.
Guest of Honor (1955)
Large mid to deep pink loose semi-double to peony form. Upright densely foliaged bush. Heavy flowering. Blooms mid season.
Guillio Nuccio (1956)
Very large deep coral pink semi-double with prominent stamens. The petals have wavy edges. Strong growing and very popular. Flowers mid season. Also available in a white and red variegated flower form.
K. Sawada (1940)
Large white rose form or formal double. Dense bushy growth. Flowers mid season.
Kramer's Supreme (1957)
Large bright red full peony form. Usually fragrant. Vigorous yet compact growth. Flowers mid season.
Laurie Bray (1955)
Medium to large light pink flowers that may be single or partially petaloid semi-double. Heavy flowering, tough and adaptable. Rather open growth that benefits from shaping when young. Flowers mid season.
Man Size (1961)
Small white anemone form. A densely foliaged medium sized bush if shaped when young but may otherwise tend to somewhat open growth. Flowers heavily around mid season.
Margaret Davis (1961)
Medium sized informal double. White with petals edged deep pink to orange red. Upright growth. Flowers mid season.
Mark Alan (1958)
Large deep purplish red semi-double or peony form. Narrow petals with a petaloid centre. Upright growth. Starts early and flowers over a long season.
Midnight (1963)
Medium sized deep red semi-double to anemone form. A dense compact bush. Flowers mid season.
Mrs D.W. Davis (1954)
Very large bright pink semi-double. Densely foliaged vigorous upright growing bush. Flowers mid season.
Nuccio's Pearl (1977)
Medium sized very pale pink flushed mid pink formal double. An attractive 'airbrushed' colour effect that intensifies towards the centre and edges of the flower. A dense compact bush. Flowers mid season.
Pink Pagoda (1963)
Medium to large mid pink formal double. Slightly wavy edged petals. An upright bush. Flowers mid season.
Prima Ballerina (1983)
Medium to large semi-double. White base colour washed with soft mid pink. A dense compact bush. Flowers mid season to late.
Roger Hall (1979)
Medium sized bright red formal double. A strong growing upright bush. Starts early and flowers over a long season.
San Dimas (1971)
Medium to large deep red petaloid semi-double. Dense compact bush. Flowers early to mid season.
Tiffany (1962)
Very large loose peony form. Soft mid pink with deeper tones. Vigorous yet compact bush. Flowers mid season to late.
Reticulata
Reticulatas are usually regarded as being less hardy than other camellias but most survive New Zealand winters unscathed.
Barbara Clark (1958)
Medium sized mid pink semi-double. Vigorous grower. Starts to flower early and continues over a long season.
Brian (1958)
Medium sized deep pink semi-double. Strong upright growth. Flowers mid season to late.
Buddha (1948)
Large deep pink semi-double flowers with wavy edged petals. Strong upright growth. Flowers mid season.
Dr. Clifford Parks (1971)
Large bright red flower. The form is very variable, it ranges from semi-double to peony to anemone form. Flowers mid season.
Grand Jury (1962)
Large salmon pink peony form. A large open bush that benefits from pruning to shape when young. Flowers mid season.
Lasca Beauty (1973)
Very large light pink semi-double. Vigorous grower that is inclined to become a little open. Flowers mid season.
Pavlova (1978)
Very large bright red semi-double. A strong spreading bush. Makes a good espalier. Flowers mid season to late.
Phyl Doak (1958)
Medium to large pale pink semi-double. A dense compact bush. Starts to flower early and continues over a long season.
Sugar Dream (1984)
Medium sized mid pink anemone form. Upright growth, inclined to be somewhat open but benefits from trimming to shape when young. Early flowering.
Valley M. Knudsen (1958)
Large deep pin semi-double to peony form. Strong growing upright bush. Flowers mid season to late.
× williamsii hybrids
This fairly diverse group of hybrids results from fertilising Camellia saluensis, or a hybrid thereof, with pollen from Camellia japonica.
Anticipation (1962)
Large deep pink peony form. Strong upright growth. Flowers mid season.
Ballet Queen (1975)
Large salmon pink peony form. A densely foliaged medium sized bush. Flowers mid season to late.
Debbie (1965)
Large bright mid pink semi-double to full peony form. A dense compact bush. Flowers mid season. One of the most popular cultivars.
Donation (1941)
Large mid pink semi-double with darker veining. Vigorous yet compact. Starts early mid season and continues over a long season.
Dreamboat (1976)
A large formal double. The base colour is mid pink but has very subtle lavender and salmon pink shading. The growth is somewhat open. Flowers mid season.
E.G. Waterhouse (1954)
Medium sized light pink formal double. Strong upright growth. Flowers mid season to late. Also available with a light pink and white variegated flower.
Elsie Jury (1964)
Large deep pink full peony form. Medium sized open growing bush. May be trained as an espalier. Flowers mid season to late.
Jury's Yellow (1976)
Medium sized anemone form. White with creamy yellow petaloid centre. Dense compact growth. Starts early and flowers over a long season.
Water Lily (1967)
Medium sized formal double. Bright light pink with darker toning. The petals have distinctly rolled edges. Strong upright growth. Flowers early to mid season.
Hybrids
This catch-all group covers plants of indeterminate parentage and those that don't fit into any of the other groups. Some authorities divide the hybrids by size, particularly separating out the miniatures.
Baby Bear (1976)
Miniature light pink single. A small densely foliage bush that is very popular for container growing. Flowers mid season.
Baby Willow (1983)
Miniature white single. Very distinctive weeping growth. When grafted it makes a good weeping standard. Flowers mid season.
Cinnamon Cindy (1973)
Miniature pale pink peony form. The central petaloids may be very pale pink. Upright willowy stems. Espaliers well. Flowers early to mid season.
Cornish Snow (1950)
Small white tinted pink single flowers. Very heavy flowering. Upright open growth. Flowers mid season.
Itty Bit (1984)
Miniature light pink anemone form. A densely foliaged low growing spreading bush. Flowers mid season.
Jubilation (1978)
Large mid pink rose form double. Occasionally has darker flecked flowers. Strong upright growth. Flowers mid season to late.
Mary Phoebe Taylor (1975)
Very large mid pink peony form. Strong upright growth. Flowers early to mid season.
Nicky Crisp (1980)
Large lavender pink semi-double. Dense compact bush. Starts to flower early and continues over a long season.
Night Rider (1985)
Small deep red semi-double. Upright bush. Flowers mid season to late.
Quintessence (1985)
Miniature white single with conspicuous golden yellow anthers and white stamens. Mildly fragrant. Dense spreading growth. Very popular as a container plant. Flowers early to mid season.
Snippet (1971)
Small pale pink semi-double. Eventually a dense compact bush but somewhat open when young. Flowers mid season.
Tiny Princess (1961)
Miniature semi-double to peony form. White to very pale pink with darker tints. Slow growing and may become rather open but occasional pinching back will produce a neat low bush. Flowers early to mid season.
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