Japanese rowan

Photo: Mintleaf — Public domain · source

Survives zone 5 through 9

Harvest calendar

Best planted in early spring after your last frost, or in fall before the ground freezes, depending on your climate.

Also called nanakamado in Japan. Compound pinnate leaves turn a striking deep purple to red in autumn — showier fall colour than most rowans. Fruit is astringent like other Sorbus and best cooked rather than eaten raw. ⚠ Not just astringent: raw fruit in this group contains parasorbic acid, which causes vomiting, stomach cramps and diarrhoea if you eat any quantity of it. Cooking, freezing, drying or a hard frost converts it to harmless sorbic acid — which is exactly why every traditional recipe cooks it and why the fruit is picked after the first frosts.

Hardiness

Zone 5–9

Habit

Tree

Edible part

Fruit

Ripens

Late summer, persisting into winter

Mature size

7–10 m (23–33 ft)

Light

Full sun to part shade

Soil pH

5.0–7.0 (acid to neutral)

Environment

Temperate, cool mountain forest

Native range

Japan, the Korean Peninsula and the Russian Far East including Sakhalin — cool temperate forest, mountain slopes and volcanic soils.

Status

Both wild and cultivated

Years to fruit

4–6 yrs

Growth speed

Moderate

Spacing

500 cm (197 in) apart — about 25 m² (269 sq ft) per plant

Leaf shape

Pinnate with 11–17 narrow, sharply toothed leaflets on a slender rachis, colouring scarlet and orange early in autumn — the trait it is planted for.

Root system

Fibrous and moderately deep, spreading wider than the crown, with a tendency to sucker in some species. Tolerant of poor and thin soils but not of compaction or drought once established.

Fruit description

Bright orange-red pomes, about 8 mm across, persisting into winter

Propagation

Seed after cold stratification. Worth knowing which kind you have: the apomictic whitebeams and their relatives set seed asexually and come true, while the sexual rowans do not and their seedlings vary. Named clones are grafted, usually onto S. aucuparia.

Pollination

Hermaphrodite and insect-pollinated. A sexual rowan rather than one of the apomictic whitebeams, so seedlings vary and a second tree improves set.

The edible parts listed above are a starting point, not a field guide. Identify a plant with certainty — ideally against a local authority — before eating any part of it, and read the full disclaimer. Spotted something wrong? Report it.