Chinese quince

Identification and origin

Pseudocydonia sinensis belongs to the Rosaceae family, the family of apples, pears and quinces. It is the only species in its genus. You will still find it under its older names, Chaenomeles sinensis or Cydonia sinensis. Its native range lies in central, southern and southeastern China; it has been introduced to Japan, Korea and California.

In cultivation, it is a small tree or a large, dense shrub, upright at first and then rounded, 10–19.5 ft tall and 5–15 ft wide, often with several trunks. It grows slowly: expect ten to twenty years for it to reach its mature size. In regions with long, hot summers, it can become a true tree and grow much taller.

Its bark is its greatest asset: it flakes off in patches, like sycamore bark, and on the fluted trunks of older trees it forms a mosaic of gray, green, brown, orange and yellow. The leaves are alternate, oval to elliptical and 2–4 in long; they are glossy, dark green and finely toothed, with each tooth ending in a tiny gland. Tinged red as the buds break, they take on shades of yellow, orange and red before they fall. They are usually deciduous, sometimes semi-evergreen.

In spring, it bears single, cup-shaped flowers, pink with a white base, 1–2 in across and very fragrant, on the previous year’s wood. They develop into a large oval fruit, a quince 4–6 in long, green at first and then lemon yellow when it ripens in fall, with a sweet fragrance. It fruits most heavily after a hot summer. It is reminiscent of flowering quince (Chaenomeles), its close relative.

In the garden, it is planted as a specimen tree, in a courtyard or small city garden, in a border or at the base of a wall, so you can enjoy its ornamental bark, fragrant flowers, fall color and fruit all year round.

Light

Full sun, with at least six hours of direct sunlight a day: that is what it takes for good flowering, well-ripened fruit and vivid fall color. In regions with cool summers, plant it in a sheltered spot against a south- or west-facing wall to give it the extra heat its fruit needs.

Watering

It prefers soil that is moderately moist to moist, but always well drained, and it tolerates some drought once established. After planting, water deeply as soon as the soil dries out a short way down, until the roots get established.

In a container, the water supply is limited: check the potting mix often and water as soon as the surface dries, until water runs out of the bottom. Its needs peak in summer, when the tree is carrying fruit; at that point, the root ball should never dry out.

Potting mix

Fertile, loamy, well-drained soil suits it best. It still copes with clay soils, soils rich in organic matter or poor soils, and it accepts acidic, neutral or alkaline pH, with a slight preference for moist, acidic soils. In a container, choose a free-draining potting mix that is neutral to slightly acidic.

Temperature

In the ground, Chinese quince withstands cold of around 23 °F to 14 °F and survives in most temperate regions. At the edge of its hardiness range, plant it out of the way of winter winds and cold, against a wall or in a protected corner. It does its best under long, hot summers.

In a pot, the roots are more exposed: protect the container from hard frost and cold winds, for example in a cold frame.

Repotting

It transplants easily. Plant it in loosened, well-drained soil in the sun, and water regularly during the first season.

In a container, repot in early spring, before the buds break: every two years for a young tree and every three to five years for an older one, replacing the potting mix and shortening any roots that are too long.

Pruning

It takes pruning well, but its flowers form on the previous year’s wood, so hard pruning cuts down on flowers and fruit. Prune right after flowering, then, and limit yourself to thinning out crossing branches, dead wood and badly placed shoots.

As bonsai, its pruning follows its own set of rules, covered in detail in the Chinese quince bonsai guide.

Propagation

Seed is the usual method: sow the seeds in a flat outdoors in fall so they spend the winter in the cold. You can also take softwood cuttings in summer or use air layering.

Common problems

It is generally rarely attacked. Still, a single symptom can have several causes: look over the whole tree before treating.

• Shoots and flowers turning black as if scorched: fire blight, the most serious disease for this tree, which calls for close watching.
• Brown spots on the leaves, early leaf drop: quince leaf blight (entomosporium leaf spot).
• Fruit rotting on the tree: brown rot (monilinia).
• White, felty coating on the leaves: powdery mildew.
• General decline: armillaria root rot can attack the tree wherever this fungus is present.
• Pests: aphids, scale insects and weevils sometimes appear, especially on potted trees.

Toxicity

No toxicity has been reported: Chinese quince does not appear among the plants that veterinary references list as toxic to dogs and cats. Its fruit is edible and is mainly used to make jams and jellies.