Walnut

Profile

Family

Juglandaceae

Habit

Tree

Height

25 m

Spread

25 m

Growth

fast

Lifespan

150 years

First yield

after 8 years

Hardiness

zone 6–9

Shade tolerance

full sun

Soil

Sand, Silt, Loam, Clay

Soil moisture

dry – very moist

pH

5 – 8.5

Synonyms

Walnussbaum

Planned in gardens

8×

Flowering & harvest

Times apply to the northern hemisphere in a temperate climate and shift with altitude and cultivar.

Uses

Edible: Pickled fruit, raw and germinated seeds – 1.8 tons per hectare, equivalent to around 1,290 calories per square meter. Oil can be obtained from the seeds. The tree sap is useful, and the leaves can be used for tea or as a pepper seasoning.

Medicinal: Leaves - purify blood, aid in constipation, diarrhea, chronic cough, and asthma. Bark - relieve pain, assist with diarrhea and anemia. Seeds - strengthen, deworm (oil), aid in weakness in legs and skin issues. Bach flower - assist with lack of self-confidence.

Other uses: Dyeing: Catkins and fruit skin turn yellow, while nutshell and leaves become brown. Nut oil and wood polish extracted from the kernel are used to fill imperfections. Fruit skin is dried for wood painting, and leaves serve as insect repellents. The bark, rich in tannin, also acts as a tooth cleaner. The wood is heavy, hard, durable, and quick to dry.

Growing

Erfordert einen tiefen, gut durchlässigen Lehm und eine sonnige Position, die vor starken Winden geschützt ist. Bevorzugt einen leicht alkalisch schweren Lehm, ist aber auf den meisten Böden erfolgreich. Der Walnussbaum verträgt Berichten zufolge einen jährlichen Niederschlag von 31 bis 147 cm, eine jährliche Temperatur im Bereich von 7,0 bis 21,1 ° C und einem pH-Wert im Bereich von 4,5 bis 8,2. Die ruhende Pflanze ist sehr kältetolerant und verträgt Temperaturen bis zu etwa -27 ° C ohne ernsthafte Schäden. Das junge Frühlingswachstum ist jedoch eher zart und kann durch späten Frost beschädigt werden. Es wurden einige spätblättrige Sorten entwickelt, die häufig Schäden durch Frühlingsfröste vermeiden und einen Holzbaum von besserer Qualität hervorbringen können.

Propagation

Sow seeds immediately after harvesting in deep pots in a cold frame. Protect from animals. Seeds typically sprout in late winter or early spring. Transfer seedlings outdoors. They will settle in by early summer, offering some winter protection. Alternatively, store seeds in cool, moist conditions over winter and plant in spring. Cold stratification might be necessary for germination.

Value for wildlife

Provides pollen and nectar for various insects, especially during spring flowering. The leaves, rich in tannins, are less attractive as food for many insects. The fruits serve as food for birds and small mammals. Its dense crown offers shelter and nesting sites for birds. The fallen leaves and chemical compounds in the soil affect surrounding vegetation and indirectly influence local wildlife.

Notable

Special features: One crop was able to completely supply itself with the walnut tree. Half-ripe nuts and early summer leaves contain 1% vitamin C! The leaves are very rich in tannins and are allelopathic, meaning they compost slowly and are avoided by insects. The leaves only shade the trees in early summer. Scandinavian walnuts only bloom from June onwards, meaning there is no risk of late frost. They prefer warmth and wind protection. They have a very good ratio of omega 3:6 fatty acids, ~2.1% in German forests; 1500 kWh/m²; 4.1 kWh/kg.

Origin & habitat

Originally, the forest population was in Kyrgyzstan. Today, with the help of squirrels, it can be found everywhere, scattered along forest edges, in reforestation areas, or other fallow areas.

Himalayan forests

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