Pinus Thumbergii

Class

Conifers

Division

Pinophyta

Family

Pinaceae or Pinaceae

Order

Pinales

Genus

Pinus

Species

thunbergii

Description

An evergreen conifer belonging to the botanical family Pinaceae, widely appreciated in the world of bonsai where it takes on a primary role due to its elegant plant architecture with an enlarged foliage bearing deep green needle-shaped leaves, and a woody stem furrowed by distinctive dark bark. Long-lived, it tolerates wind and temporary drought, requiring bright exposures and a specific well-draining soil.

Variety description

Pinus thumbergii, is an evergreen conifer native to Japan and Korea. It is one of the most popular pine species for the art of bonsai due to its robustness, decorative bark and majestic bearing. The foliage is broad, irregular with horizontal, strongly branched branches. Knotty trunk with thick, deeply furrowed dark grey-black bark, hence the common name 'black pine'. Needles are arranged in pairs (bundles of 2), stiff and pointed, 7-12 cm long, bright dark green. Taproot that grows deep

Curiosities and special features

The specific epithet thunbergii was given in honour of the Swedish botanist and entomologist C. P. Thunberg.

The art of bonsai, i.e. the technique of growing miniature trees, has very ancient origins. It originated in China and spread to Japan, taking on profound meanings that reconcile philosophical and spiritual principles, in search of a symbiosis between man and nature. Today, also thanks to cultural exchanges and international events in the sector, bonsai cultivation has developed throughout the West.

Origin and distribution

Native species of Korea, central and southern Japan.

Leaf

The leaf blades are needle-shaped, rigid and pointed. The needles are arranged in pairs (bundles of 2).

Leaf colour

Solid colour, bright dark green.

Plant height

The height of the plant varies from 0.25 to 1.5 m, depending on the growing conditions and environment.

Lifespan

Evergreen Perennial Species.

Where to plant

Suitable as a plant for large pots, small pots, depending on the age of the specimen.

Stem

The stem is woody and gnarled, with thick, cracked, deeply furrowed dark grey-black bark, hence the common name 'black pine'.

Growth

Compact Growth Plant.

Plant habit

Upright habit with broad foliage.

Branching

It develops medium branching with horizontal branches.

PH

It requires a pH of the growing and cultivation substrate between 4.5 and 5.5.

Sun exposure

Choose exposures in half shade, full sun. The plant should be turned regularly in the direction of light so that it develops evenly. In summer, shade if temperatures rise too high, above 30°C. Check that the lower branches also receive light, turning the plant occasionally if the light source comes from one direction.

Ideal climate and temperature

The ideal temperature is between 5 and 20 °C. The vital temperature is between -20 and 40 °C. It has good frost resistance, but the roots must be protected.

Use

Species valued for its plant architecture in:

Outdoor ornamental

Widely cultivated as bonsai.

Hardiness

It ishighly rustic, tolerant to salt, wind and quite drought-tolerant.

Soil

Choose new, high quality bonsai-specific soil. Prefers well-drained soil.

Difficulty

The cultivation of Japanese black pine is difficult on average, with a medium level of management effort required. By taking the correct cultivation care with regard to fertilisation, irrigation and pruning, excellent vegetative growth results will be achieved.

Growing tips

Some specific cultivation tips for better vegetative development:

Avoid over-watering Prefers shady locations in summer to avoid dry spells and high afternoon temperatures Prefers slightly calcareous water Exposure to direct light

Pruning

Perform tillering or training pruning as well as cleaning the vegetative part. It is recommended to let the year's shoots grow until mid-August, then shorten to 3-4 mm.

Propagation

Propagation is by layering or by cuttings.

Repotting

Repot every 2-5 years, depending on the age of the plant.

Watering

With the plant in vegetation, from early spring, water regularly, keeping the soil fairly moist but carefully avoiding waterlogging. From the end of autumn and in winter reduce the quantity, also allowing the soil to dry out slightly between watering in order not to damage the roots, which are delicate and need to be protected, with frost. Apply low-lime water with an optimal acidic pH value and low salinity to the pot under the foliage.

Fertilising

Fertilise when the shoots start to move, using specific Japanese organic fertiliser in granules; discontinue from the beginning of October. Spreading should be done in the pot under the foliage, lightly inserting the granules into the soil.

Edibility for humans

Non-edible.

Tip

Position the plant in full light. In summer, shade if temperatures rise too high, above 30°C. Check that the lower branches also receive light, rotating the plant from time to time if the light source comes from one direction. With the plant in vegetation, from the beginning of spring, water regularly, keeping the soil fairly moist at all times. From the end of autumn and in winter reduce the quantity, also allowing the soil to dry out between waterings in order not to damage the roots, which are delicate and need to be protected, with frost. Fertilise when the shoots start to move, using specific Japanese organic fertiliser in granules. Discontinue from the beginning of October.