Tree of Life

Healthy Home Gardening
English Walnut
Juglans regia

Type Categories Useful Parts


Juglandaceae Family

Juglans Genus
Other Names for this Plant

Common walnut, Persian walnut


Native to E. Europe to N. Asia. In a region stretching from the Balkans eastward

to the Himalayas and southwest China

Physical Description
Juglans regia is a large deciduous tree attaining heights of 2535 m, and a trunk up to 2 m diameter, commonly with a short trunk and broad crown, though taller and narrower in dense forest competition. It is a light-demanding species, requiring full sun to grow well.

The bark is smooth, olive-brown when young and silvery-grey on older branches, with scattered broad fissures with a rougher texture. Like all walnuts, the pith of the twigs contains air spaces, the chambered pith brownish in colour. The leaves are alternately arranged, 25-40 cm long, odd-pinnate with 59 leaflets, paired alternately with one terminal leaflet. The largest leaflets the three at the apex, 1018 cm long and 68 cm broad; the basal pair of leaflets much smaller, 58 cm long, the margins of the leaflets entire. The male flowers are in drooping catkins 510 cm long, the female flowers terminal, in clusters of two to five, ripening in the autumn into a fruit with a green, semi-fleshy husk and a brown corrugated nut. The whole fruit, including the husk, falls in autumn; the seed is large, with a relatively thin shell, and edible, with a rich flavor.

General Information

The walnut was introduced into western and northern Europe very early, by Roman times or earlier, and to the Americas by the 17th century, by English colonists. Important nut-growing regions include France, Serbia, Greece, Bulgaria, and Romania in Europe, China in Asia, California in North America, and Chile in South America. Lately the crop has spread to another regions: New Zealand and southeast of Australia. It is cultivated extensively for its high-quality nuts, eaten both fresh and pressed for their richly flavoured oil; numerous cultivars have been selected for larger nuts with thinner shells.

Introduced from Spain by way of Chile to California about 1867. In 1873 'Kaghazi' was introduced in northern California and a seedling 'Eureka' has become the important source of our commercial varieties.

Medicinal Uses: The walnut tree has a long history of medicinal use, being used in folk medicine to treat a wide range of complaints. The leaves are alterative, anthelmintic, anti-inflammatory, astringent, and depurative. They are used internally the treatment of constipation, chronic coughs, asthma, diarrhea, dyspepsia etc. The leaves are also used to treat skin ailments and purify the blood. They are considered to be specific in the treatment of strumous sores. Male inflorescences are made into a broth and used in the treatment of coughs and vertigo. The rind is anodyne and astringent. It is used in the treatment of diarrhea and anemia. The seeds are antilithic, diuretic and stimulant. They are used internally in the treatment of low back pain, frequent urination, weakness of both legs, chronic cough, asthma, constipation due to dryness or anemia and stones in the urinary tract. Externally, they are made into a paste and applied as a poultice to areas of dermatitis and eczema. The oil from the seed is anthelmintic. It is also used in the treatment of menstrual problems and dry skin conditions. The cotyledons are used in the treatment of cancer. Walnut has a long history of folk use in the treatment of cancer; some extracts from the plant have shown anticancer activity. The bark and root bark are anthelmintic, astringent, and detergent.

Food Uses: Seed - eaten raw or used in confections, cakes, ice cream etc. A delicious flavor. The seed can also be ground into a meal and used as a flavoring in sweet and savory dishes. The unripe fruits are pickled in vinegar. An edible oil is obtained from the seed, it should not be stored for any length of time since it tends to go rancid quickly. The oil has a pleasant flavor and is used in salads or for cooking. The sap is tapped in spring and used to make a sugar. The finely ground shells are used in the stuffing of 'agnolotti' pasta. They have also been used as adulterant of spices. The dried green husks contain 2.5 - 5% ascorbic acid (vitamin C) - this can be extracted and used as a vitamin supplement. The leaves are used as a tea

The plant is used in Bach flower remedies - the keywords for prescribing it are 'Oversensitive to ideas and influences' and 'The link-breaker'

Other Notes: A yellow dye is obtained from the green husks. It is green. The green nuts (is this the same as the green husks?) and the leaves are also used. The rind of unripe fruits is a good source of tannin. A brown dye is obtained from the leaves and mature husks. It does not require a mordant and turns black if prepared in an iron pot. The dye is often used as a coloring and tonic for dark hair. The leaves and the husks can be dried for later use. A golden-brown dye is obtained from the catkins in early summer. It does not require a mordant.

In Skopelos, a Greek island in the Aegean Sea, local legend suggests that whoever plants a walnut tree will die as soon as the tree can "see" the sea. This has not been proven as fact, however it might take some time to find a local arborist willing to take on the job of planting a walnut tree. Most planting is done by field rats (subfamily Murinae).

In Flanders, the saying (in Dutch) goes "Boompje groot, plantertje dood", meaning "By the time the tree is big, the planter sure will be dead". The saying refers to the relatively slow growth rate of the tree

Cultivation: Requires a deep well-drained loam and a sunny position sheltered from strong winds. Prefers a slightly alkaline heavy loam but succeeds in most soils. The walnut tree is reported to tolerate an annual precipitation of 31 to 147cm, an annual temperature in the range of 7.0 to 21.1°C and a pH in the range of 4.5 to 8.2. The dormant plant is very cold tolerant, tolerating temperatures down to about -27°C without serious damage, but the young spring growth is rather tender and can be damaged by late frosts. Some late-leafing cultivars have been developed; these often avoid damage from spring frosts and can produce a better quality timber tree. The walnut tree is frequently cultivated for its edible seed in temperate zones of the world, there are many named varieties. Newer cultivars begin producing nuts in 5 - 6 years; by 7 - 8 years, they produce about 2.5 tons of nuts per hectare. Orchards on relatively poor, unirrigated mountain soil report 1.5 - 2.25 tons per hectare, orchards in well-cultivated valleys, 6.5 - 7.5 tons per hectare. According to the Wealth of India, a fully-grown individual can yield about 185 kg, but 37 kg is more likely. Trees grow well in most areas of Britain but they often fail to fully ripen their fruits or their wood in our cooler and damper climate, they prefer a more continental climate. There are some very fine trees in Cornwall. Walnuts can produce large healthy trees in many parts of Britain, but seedling trees often do not fruit reliably. Some European varieties have been developed that succeed in colder areas. Seedling trees are said to take from 6 to 15 years to come into fruit from seed, but these cultivars usually start cropping within 5 years. Plants produce a deep taproot and they are intolerant of root disturbance. Seedlings should be planted out into their permanent positions as soon as possible and given some protection for their first winter or two since they are somewhat tender when young. Flower initiation depends upon suitable conditions in the previous summer. The flowers and young growths can be destroyed by even short periods down to -2°c, but fortunately plants are usually late coming into leaf. Some cultivars are self-fertile, though it is generally best to grow at least two different cultivars to assist in cross-pollination. Any pruning should only be carried out in late summer to early autumn or when the plant is fully dormant otherwise wounds will bleed profusely and this will severely weaken the tree. Plants produce chemicals which can inhibit the growth of other plants. These chemicals are dissolved out of the leaves when it rains and are washed down to the ground below, reducing the growth of plants under the tree. The roots also produce substances that are toxic to many plant species, especially apples (Malus species), members of the Ericaceae, Potentilla spp and the white pines (certain Pinus spp.). Trees have a dense canopy which tends to reduce plant growth below them. All in all, not the best of companion trees, it is also suggested that the trees do not like growing together in clumps. Trees are said to inhibit the growth of potatoes and tomatoes. Hybridizes with J. nigra. This species is notably susceptible to honey fungus. The bruised leaves have a pleasant sweet though resinous smell

Propagation: The seed is best sown as soon as it is ripe in individual deep pots in a cold frame. You need to protect it from mice, birds, squirrels etc. The seed usually germinates in late winter or the spring. Plant out the seedlings into their permanent positions in early summer and give some protection from the cold for their first winter or two. The seed can also be stored in cool moist conditions (such s the salad compartment of a fridge) over the winter and sown in early spring but it may then require a period of cold stratification before it will germinate. Named varieties are propagated by budding.

English Walnut
Koehlers Medicinal-Plants 1887 [Image in Public Domain]

Comment: English Walnut, Juglans regia

Look for English Walnut on:
Google: English Walnut Wikipedia: English Walnut YouTube: English Walnut
Phylogenetic Tree of Life

Learn how to create a custom
Tree of Life

© Copyright 2006 - 2020 HealthyHomeGardening.com.
All Rights Reserved.
Web Design by Artatom