Black Walnut (juglans nigra)

• North American introduction (1629), grown for highly prized dark timber (furniture, gunstocks) and potential agroforestry value.
• Produces edible nuts with rich, earthy flavour (though thick-shelled and harder to extract than common walnut).
• Attractive large pinnate leaves turning yellow in autumn; fragrant foliage; broad crown for shade.
• Fast-growing on good sites; long-lived; potential high-value crop/tree in warmer climates.
• Caution: roots/leaves/nuts exude juglone, high Toxicity to many plants (e.g., tomatoes, apples, potatoes) – limits underplanting and companion gardening.

Planting Guide

• Best time: Bare-root November–March (dormant season); container-grown autumn or spring.
• Location: Full sun; deep, fertile, moist but well-drained soil (tolerates most except waterlogged or very acid); sheltered, frost-free site in warmer southern/lowland UK – needs ample space (matures 20–30m+ tall/wide, unsuitable for small gardens).
• Preparation: Dig large hole twice root ball width; add organic matter to poor soils; keep area weed-free initially.
• Planting: Set at original depth (check trunk soil mark); stake young trees; firm in and water well, mulch base to control weeds and preserve water (keep clear of trunk).
• Aftercare: Water regularly first few years in dry spells; minimal pruning (winter for form); difficult to establish in areas prone  to late spring frosts; low-maintenance once established.