The weird and wonderful Japanese raisin tree
It looks like a fruit from another world, brown and knobbly and forked like a twig. The Chinese have long known of its restorative power on the liver and used it as an antidote for alcohol. But best of all it belies its looks and tastes just like it sounds – sweet and tasty with the slightly chewy consistency of a raisin.
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The Japanese raisin tree is not just a producer of weird and wonderful fruit, it is also an attractive and low-maintenance tree. Endemic to east Asia – from China to the Himalayas – and found growing up to 2000m above sea level, it will grow anywhere in New Zealand with adequate moisture. Some call its tendency to self-prune an advantage, as it will naturally shed its lower branches to grow into a graceful, spreading tree. However, if you have ever tried to utilise its restorative powers with a hangover, you may not think so as you negotiate harvest with a pole pruner from the top of a ladder.
The edible ‘fruit’, which looks like thick contorted twigs (akin to skinny ginger roots) is actually composed of the swollen flower stalks (pedicels). The true seed is borne in pods on the end of these swollen stalks, itself inedible.
In autumn to early winter, the stalks are harvested when they turn reddish-brown and the seedpods grey-brown. They can be picked directly from the tree (a long-handled pole pruner is of great assistance) or gathered from the ground when they drop.
Consume the fruit fresh, store in a paper bag in a dark cupboard for up to two months (the flavour apparently improves during this time) or dehydrate and use in place of actual raisins or other dried fruits. Eaten fresh, the stems have a crunchy texture and the flavour of raisins with hints of apple and pear.
H. dulcis has long been used in traditional Chinese medicine, with emphasis on treating liver complaints and the consumption of excess alcohol. Several active compounds have been scientifically identified and are under investigation, showing potential for treating a number of medical conditions. One of these is dihydromyricetin, which has been utilised in anti-alcohol medication and demonstrates liver-protective qualities. There is anecdotal evidence it potentially may be useful for treating neurological disorders such as Alzheimer’s and Parkinson’s diseases and anxiety-related conditions, with the added advantage of being non-addictive. A honey substitute is produced from the young limbs and leaves, hence the common name ‘honey tree’.
Flowering takes place from late spring to early summer, depending on the climate. Large clusters of tiny fragrant cream-coloured, nectar-rich flowers are produced, which are highly attractive to pollinators, although not required, the flowers are hermaphroditic and therefore self-fertile.
And at the end of the day, if you need to cut it down, its hard, fine-grained timber is prized for construction and furniture.
Quick facts
Plant family: Rhamnaceae (buckthorn family)
Also known as: Chinese chi-chao li, ‘chicken-claw pear’; Japanese kenpō nashi (ken = fist); honey tree
Relatives include: Jujube (Chinese date), Darling plum (red ironwood)
Where to plant
H. dulcis is a fast-growing deciduous tree, averaging 10 metres in height at maturity.
It withstands temperatures down to -30°C so should grow well throughout New Zealand, although in colder regions flowering may occur later and/or there may not be sufficient heat to ripen the stems before winter. Plant in full sun in these cooler areas. Tender spring growth may be hit by late frosts, but usually recovers.
It is tolerant of a range of soil types, doing best in fertile loams with adequate moisture, though avoid heavy soils prone to waterlogging. Young trees will require wind protection.
Coastal locations should be avoided, as should hot, dry, exposed sites in warmer climates.
Maintenance
In general, H. dulcis is a literal plant-and-walk-away species, requiring minimal fertiliser and is not known to be susceptible to any particular diseases or insect pests.
How to source
H. dulcis can be propagated from seed, but the process requires scarification, heat, and humidity for successful germination. Vegetative propagation is possible via semi-hardwood or root cuttings. Seedling trees may take up to 10 years to produce; their cutting-grown counterparts can fruit three years from establishment. Plants are readily available commercially via Incredible Edibles and independent nurseries.
Anna-Marie Barnes is the New Zealand Tree Crops Association’s South Island Vice-President. She holds a Bachelor of Science (Primary Production) with a background in agroecology and entomology, and a Graduate Diploma of Teaching and Learning (Secondary). A lifelong gardener, she is a dedicated self-sufficiency enthusiast and endeavours to grow as much of her own produce as possible. She is a keen soapmaker, baker, cheesemaker, and preserver, and takes great delight in bartering ‘homestead goods’ with friends. She lives on a lifestyle block in the Tasman region with three unruly Orpington hens.
