What Will Grow Under a Walnut Tree?

Ground Covers and Vines

• Choose shade- and juglone-tolerant ground covers and vines to plant beneath your walnut tree's canopy. Options include Virginia creeper (Parthenocissus quinquefolia), a North American native that thrives in partial to full shade and sites with juglone. This creeping vine grows from 30 to 50 feet and has bronze to deep green foliage. Virginia creepers produce blue, bird-attracting berries in fall and tolerate a range of soils. Japanese pachysandra or spurge (Pachysandra terminalis) can grow beneath walnut trees. This evergreen ground cover grows from 6 to 10 inches tall and forms a dense mat of lustrous, dark green, serrated foliage. Spurge prefers partial to full shade and moist, slightly acidic and well-drained soil.

Perennials

• Perennials add color and texture with their bright blooms. Juglone-tolerant species that can grow in light to partial shade include bugle weed (Ajuga reptans), a small, 9-inch-tall perennial that blooms with blue and white blossoms in early to late spring. Bugle weed thrives in partial to full shade and well-drained soil. The cranesbill geranium (Geranium sanguineum) tolerates drought but prefers moist soil. This 1-foot-tall plant produces deep pink flowers through spring and summer and grows in partial shade. Several species of violets (Viola spp.) grow in juglone sites, including horned violet (V. cornuta), woolly blue violet (V. sororia) and Canada violet (V. Canadensis). These tiny, 4- to 8-inch perennials bloom in spring and thrive in partial to full shade. Plant violets in moist, well-drained soil.

Deciduous Shrubs

• Deciduous shrubs lose their foliage in the winter. Choose shade-tolerant species such as the Korean spice viburnum (Viburnum carlesii), a slow-growing shrub that reaches heights of 4 to 6 feet. Korean spice viburnum produces clusters of fragrant, pink blossoms in spring, followed by red to black berries in late summer. They grow in partial shade and well-drained soil. The autumn olive (Elaeagnus umbellata) grows to 15 feet tall with a similar spread and prefers light shade. Autumn olives tolerate juglone, drought, heat, wind and sandy soils. These shrubs bloom with aromatic, funnel-shaped white flowers in late spring and produce bird-attracting red berries in fall.

Evergreen Shrubs

• Evergreen shrubs keep their foliage year-round. Juglone-tolerant species include the spreading euonymus (Euonymus kiautschovicus), which grows from 8 to 10 feet tall and grows in partial shade. This evergreen tolerates a range of soil types but grows best in well-drained sites. The spreading euonymus has deep green foliage and produces showy, pink and orange fruits in fall. Mops and Slowmound mugo pines (Pinus mugo "Mops" and "Slowmound") tolerate both juglone and partial shade. These dwarf evergreens grow slowly to 3 feet tall and require little maintenance once established. Mugo pines prefer deep, well-drained and loose soils, but adapt to a variety of conditions. They have stiff, curved, bright green needles.