Black Walnut


Juglans nigra

The black walnut is a large deciduous tree attaining heights of 98–131 feet. Under forest competition, it develops a tall, clear trunk; the open-grown form has a short trunk and broad crown. The bark is grey-black and deeply furrowed. The pith of the twigs contains air spaces.The tree tends to crop more heavily in alternate years. Fruiting may begin when the tree is 4–6 years old, however large crops take 20 years. Total lifespan of J. nigra is about 130 years. Black Walnut does not leaf out until late spring when the soil has warmed and all frost danger is past.

Feed: Measure the trunk thickness at breast height. For each inch, scatter four pounds of 10-10-10, up to a maximum of 25 lbs. under the tree branches. Do this in late March just before leaves appear.

Notes : The roots, nut husks, and leaves secrete a substance into the soil called juglone that is a respiratory inhibitor to some plants.


Height: 130 feet

Spread: 65 feet

Blooming: One of the last trees to leaf in the Spring. Will drop leaves in a drought.

Soil Moisture: Water in Drought

Sun Exposure: Full Sun