Native to southern Europe but widely planted further north for nuts and timber including in southern Britain.
Limited provenance trials have been undertaken suggesting that preferred material should be late flushing varieties identified in French breeding programmes. Unless interested in growing walnuts for the nuts, avoid using material sourced from open grown trees which often have poor form.
This is a light demanding species adapted to warm climates and fertile soils and which is very vulnerable to spring and autumn frosts. It produces a very high value timber on suitable sites. It is not tolerant of exposure. It should be planted on rich to very rich soils of fresh to moist moisture status, including alkaline soils of adequate rooting depth. It is not suited to very dry or nutritionally very poor soils, and very moist to very wet soils should be avoided. It can helpfully be grown in mixture with nitrogen fixing trees or shrubs.
Pests and pathogens
Considered particularly susceptible to Armillaria root rot (honey fungus).
While it is likely to remain confined to lowland parts of Britain, climate warming should increase the range of suitable sites for this species in northern England, Wales, and parts of Scotland.