- Type
- Trees & Vines
- Difficulty
- Moderate
- Season
- Spring·Fall
- Sowing
- Plant a sapling
Japanese Cornel (Sansuyu)
Cornus officinalis
Iridoid glycosides · yellow flowers in early spring
Sansuyu is a small deciduous tree in the dogwood family, Cornus officinalis — the Asiatic dogwood or Japanese cornel, a different species from the European cornelian cherry, Cornus mas. Its yellow flowers cluster at every branch tip in March, well before the leaves. The fruit ripens in October and November into oblong red drupes; the stone is removed and only the flesh is dried. Old orchards around Uiseong in North Gyeongsang and Sandong in Gurye, South Jeolla draw crowds every spring for the bloom. In cities it is a common street and park tree, recognisable by the March yellow and the red fruit that hangs into winter. The Donguibogam lists it in the Wood section as 山茱萸, giving a slightly warm nature, a sour and astringent taste and no toxicity, and states that from one geun of dried fruit the correct yield is four nyang of flesh and skin once the stones are discarded.
Year-Round Calendar
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Where It Grows
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Main producer
Long-established growing areas are found in Sandong in Gurye, South Jeolla, and in Uiseong, North Gyeongsang; Yangpyeong in Gyeonggi and Namwon in North Jeolla are also producing areas. Harvest October, November
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Main producer
Production centers on Xixia and Nanyang in Henan Province and Lin'an in Zhejiang Province, and China produces more of the crop than anywhere else in the world. Harvest October, November
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- Wild population Introduced trees remain in plantings here and there across the country, and it is common as an ornamental.
Its range spans the temperate zone of East Asia — Korea, China, and Japan — but commercial production effectively narrows to just two countries, Korea and China. The European cornel of southeastern Europe is a different species, with the scientific name Cornus mas; its fruit is larger and its uses differ, so it is not included on this map.
- Optimum
- 15~25℃
- Range
- 5~33℃
- Hardiness
- Hardy
A small tree of the temperate deciduous forest zone, it needs a spell of winter cold for its flower buds to open properly; the flowers appear in March, before the leaves. It withstands temperatures down to -25℃, but because it blooms early, a late frost around flowering time cuts that year's fruit crop. The best sites are mountain foothills that hold some moisture in summer yet drain well, such as land along valley streams.
Harvested 3–4 years after planting. Grafted saplings begin bearing fruit three or four years after planting. Trees raised from seed take seven to eight years to produce their first fruit. There is no harvest in the year of planting.
In Korea Central Korea and south
Growing areas lie along the mountain foothills of central and southern Korea, south of Yangpyeong in Gyeonggi. The trees flower in March, and the fruit ripens to red in October–November.
How to grow
- Light
- Six hours of direct sun or more. Short of light it flowers sparsely and fruits less
- Soil and depth
- Free-draining, fertile ground at least 50cm deep. It does best where moisture lingers, as it does beside a stream
- Spacing
- 4 to 5m apart. A mature tree reaches around 7m
- Watering
- Water through summer dry spells for the first two years. Drought in August and September, while the fruit swells, decides the size
- Feeding
- Ring well-rotted compost under the drip line after leaf fall or in early spring. Excess nitrogen just pushes leaf
- Harvest
- Pick in October and November once the fruit is fully red. Destone straight away and spread the flesh to dry in ventilated shade. Destoned flesh shrinks a great deal as it dries
What makes the difference. A seedling takes seven or eight years to its first fruit; grafted stock fruits in three or four. A single tree will set fruit, but two or more crop better
Why this one is harder. Destoning is the labour. It used to be done with the teeth; a mechanical destoner does it now. For a small pick, pressing the stones out by hand while the fruit is still soft from picking is quickest
Common problems
- Aphids You will see Colonies on new shoots and flower stalks in spring, leaves curling What to do Wash off with a jet of water; if it recurs, use an egg-yolk oil spray. Leave them be once ladybirds arrive
- Scale insects You will see White or brown shell-like bumps on branches, leaves turning sticky then sooty black What to do Scrape them off with a brush in winter; if widespread, apply a dormant horticultural oil while the tree is leafless
- Anthracnose You will see Sunken black spots on the fruit, spreading after the rainy season What to do Clear fallen and affected fruit away and thin the branches so air moves through. Never let dropped fruit pile up under the tree
This page describes how a crop is grown and used. It does not claim health effects for any food, nor is it intended to prevent or treat disease. Component and study notes are references only and do not mean the same result occurs in people. Consult a medical professional about health concerns.
Health Benefits
What the Donguibogam records — nature, taste and destoning. The Donguibogam lists the fruit in the Wood section as 山茱萸. It gives a slightly warm nature, a sour and astringent taste, and no toxicity. It says the tree is found everywhere, that its leaves resemble elm and its flowers are white — though the flowers of Cornus officinalis are in fact yellow. The fruit, it says, is red and the size of a goji berry when newly ripe and still moist, contains a stone and is worth eating; once dried the skin is very thin, and from one geun the correct yield is four nyang of flesh and skin with the stones discarded. It records gathering in the ninth or tenth lunar month, drying in shade, steeping in liquor, removing the stones and finishing over a low fire, and gives 石棗 as another name. This is a historical medical record and differs from modern medical judgment.
The modern view — as far as composition. Analyses report the isolation of iridoid glycosides such as loganin and morroniside from the fruit, with content varying by drying method and heating conditions. Other analyses attribute the sourness to organic acids such as malic and tartaric acid, and the astringency to tannin-class polyphenols. Human studies are scarce, so composition is as far as anything can be said today.
Nutrition
- Loganin and morroniside (the main iridoid glycosides of the fruit) — glycosides contributing bitterness
- Organic acids (malic, tartaric) (the basis of the sourness) — compounds behind the fruit's acidity
- Tannins (higher in underripe fruit) — polyphenols behind the astringency
- Ursolic acid (reported in the fruit skin) — a triterpene common in fruit peel
Working with the sourness Sansuyu (Cornus officinalis) stays sour to the end, so it is rarely eaten straight off the tree. It is dried, packed in sugar, or brewed, and honey or sugar goes into the brew to balance it. Sugar rises as the fruit ripens and takes a little off the edge, but it never sweetens the way an apple or a pear does.
Ripeness and astringency The less ripe the fruit, the more astringent it is. Stripped fully red, it is markedly less puckering, and drying takes a little more away. Picked in a hurry before the colour deepens, the astringency stays put.
Destoning and drying Only the flesh is used; the stones are taken out. The flesh is thin, so pressing the stone out with a fingertip works best while some moisture remains — once the fruit dries hard, the stone will not release. Slow drying in ventilated shade gives better colour than rushing it in full sun. The old text likewise says to gather in the ninth or tenth lunar month and dry in the shade.
Pairings
○ Brewed from the dried flesh — Simmer a handful of destoned dried flesh in water over low heat for about 20 minutes. The sourness is strong, so be generous with the water. Balance it with honey or sugar before drinking.
○ Fruit syrup and candied fruit — Destoned flesh layered with an equal weight of sugar makes a red syrup. The fruit is acidic enough that cutting the sugar leads quickly to spoilage. Keep it refrigerated and use it within a few months.
○ Jujube and ginger — Simmering jujube alongside adds sweetness that softens the sourness. A little ginger tidies up the aroma. Boiling all three together for long turns the liquid cloudy, so add the jujube later. Ginger · Jujube
△ Always remove the stones — The stones are hard and astringent, and biting one damages a tooth. The old record likewise says the correct yield from one geun is four nyang of flesh and skin with the stones discarded, and describes steeping in liquor before removing them. Press them out by hand while the fruit is soft right after picking, or use a destoner. Once dried, the stones do not come out easily.
△ Do not eat much fresh fruit — Fresh fruit is sharply sour and astringent, and a large amount can leave the stomach uncomfortable. Taste a couple at most and dry or sugar the rest. Tell children about the stones as well as the fruit, so bright red drupes on a street tree do not get eaten by the handful.
△ Do not confuse it with Korean spicebush — Its early yellow flowers are often mistaken for Korean spicebush (Lindera obtusiloba). Spicebush smells of ginger when a twig is snapped, has three-lobed leaves and ripens black fruit. Cornelian cherry has unlobed leaves and oblong red fruit. Do not judge on flowers alone; check leaves and fruit before picking.
Varieties
- Uiseong local line (sapling) — The long-established line around Uiseong, North Gyeongsang. Even fruit size
- Gurye Sandong local line (sapling) — The line around Sandong, Gurye in South Jeolla, with many old village trees
- Grafted stock (grafted sapling) — Brings first fruiting forward from the seven or eight years a seedling needs to three or four
Source: Donguibogam, Wood Section 山茱萸 · Rural Development Administration (Nongsaro) · Korea National Arboretum plant list