Camellia

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Camellia

Camellia
Camellia japonica natural.jpg
Genus: Camellia
Family: Theaceae
Type: Trees and Shrubs
Transplant: Transplants easily
Pollination: Insects

Camellia is a genus of flowering plants in the family Theaceae, native to eastern and southern Asia from the Himalaya east to Japan and Indonesia. There is some controversy over the number of existent species, with anything from 100–250 species being accepted. The genus was named by Linnaeus after Fr. Georg Joseph Kamel S.J., a Jesuit botanist.

Description[edit]

They are evergreen shrubs and small trees from 2–20 m tall. The leaves are alternately arranged, simple, thick, serrated, usually glossy, and 3–17 cm long. The flowers are large and conspicuous, 1–12 cm diameter, with (in natural conditions) 5–9 petals; colour varies from white to pink and red, and yellow in a few species. The fruit is a dry capsule subdivided into 1–5 compartments, each containing 1–8 seeds.

Growing conditions[edit]

The genus is generally adapted to acidic soils, and does not grow well on chalk or other calcium-rich soils. Most species also have a high rainfall requirement and will not tolerate drought.

Species[edit]

There are about 100–250 species, including:

Uses[edit]

One species, Camellia sinensis (tea), is of major commercial importance. Tea oil is a sweet seasoning and cooking oil made by pressing the seeds of Camellia sinensis or Camellia oleifera.

Many other camellias are grown as ornamental plants for their flowers; about 3,000 cultivars and hybrids have been selected, many with double flowers, as in the gallery featured below. Camellia japonica (often simply called Camellia) is the most prominent species in cultivation, with over 2,000 named cultivars; next are C. reticulata, with over 400 named cultivars, and C. sasanqua, with over 300 named cultivars. Popular hybrids include C. × hiemalis (C. japonica × C. sasanqua) and C. × williamsii (C. japonica × C. salouenensis). They are highly valued in Japan and elsewhere for their very early flowering, often among the first flowers to appear in the late winter. Late frosts can damage the flowers.

Maintenance[edit]

Camellias have a slow growth rate. Typically they will grow about 30 centimetres a year until mature although this varies depending on variety and location.

Propagation[edit]

Harvesting[edit]

Pests and diseases[edit]

Leaf Spot

  • Cercospora theae (in greenhouse conditions)
  • Pestalosa guepini
  • Phyllosticta camelliae
  • Phyllosticta camelliaecola
  • Sphaceloma
  • Sporonema camelliae

Black Mold

  • Meliola camelliae

Leaf Gall

  • Exobasidium camelliae

Flower Blight

  • Botrytis cinerea
  • Sclerotinia camelliae
  • Sclerotinia sclerotiorum

Canker

  • Glomerella cingulata

Root Rot

Leaf Blight

  • Cephaleuros virescens

Viruses: Variegation may be caused by a virus which vectors through grafting.

Bud drop: Caused by insufficient light, high temperatures before bloom, rootbinding, overwatering, sever freezing.

Chlorosis

Oedema-Caused by overwatering

Sunburn -Too much light

Salt injury

Nematodes

Aphids

Scales

Whiteflies

Mealybugs

Thrips

Beetles

Mites

Gallery[edit]

References[edit]