Princess tree

Profile

Family

Paulowniaceae

Habit

Tree

Height

15 m

Spread

10 m

Growth

very fast

Lifespan

100 years

First yield

after 9 years

Hardiness

zone 6–9

Shade tolerance

full sun

Soil

Sand, Silt, Loam

Soil moisture

dry – very moist

pH

5 – 8.9

Synonyms

Kiribaum, Kiri,

Flowering & harvest

Times apply to the northern hemisphere in a temperate climate and shift with altitude and cultivar.

Uses

Edible: Use flowers raw in a salad with miso and cook the leaves as an emergency food.

Medicinal: Flowers: for skin conditions; leaves: poultices for bruises; decoctions for washing sores; leaf juice for warts and intestinal parasites; inner bark: tincture for fever and delirium.

Other uses: Leaves for animal feed; wood 70 fm/ha/a (lighter, harder, stronger than spruce, flame-resistant, easy to work, does not splinter, good thermal insulation, beautiful, insect-resistant); used in house, ship, sauna construction, surfboards, furniture, tool handles, musical instruments; also for firewood, charcoal (fireworks), humus formation, decoration, and fragrance.

Growing

Requires deep, moderately fertile, moisture-retaining, and well-drained soil in a sunny, sheltered area. The plants can withstand air pollution. It is a highly decorative and rapidly growing plant. Flower buds develop in autumn and may start growing prematurely in mild winter conditions, increasing their vulnerability to frost. The flower buds are resilient to about -15°C when inactive. Young plants, particularly seedlings under 2 years old, are prone to frost damage. They may not bloom reliably in coastal regions, likely due to insufficient warmth and dryness in the summer. The branches have a tendency to break easily. The flowers emit a delicate, pleasant scent. Trees can be pruned annually, leading to vigorous growth with leaves reaching up to 1 meter in width. Plants in this genus show remarkable resistance to the honey fungus.

Propagation

Seeds should be sown right after reaching maturity in a cool environment. For stored seeds, sow them in a greenhouse at 15-20°C during late winter. Light is necessary for the seeds to germinate, with a fair to good germination rate. Once the seedlings are sufficiently grown, transfer them to individual pots and let them develop in the greenhouse during their first winter. By late spring or early summer, after the final frosts, plant them in their permanent spot. In July/August, take cuttings from semi-mature wood, 5-8 cm long with a heel, and place them in a frame. Overwinter the cuttings in a cool environment during the first year and plant them out in late spring. Root cuttings of 4 cm in length can be taken in December, with a high success rate.

Notable

Special features: offers slope erosion protection + rich mulch; needs wind protection & draining, light, preferably deep/disturbed soils; likes hot summers; planted in Japan for the birth (of a daughter) & felled + carpentered for the wedding; Kiri (Japanese = cutting) → short rotation; aggressive roots! Hybrid breeding. Nordmax21® world record; 6m/year; + agroforestry;

Origin & habitat

E. Asia - China.

Forests, scrub, and hedges typically found on alkaline soils, reaching altitudes of up to 840 meters.