Home > Advice > Ornamental Tree Advice > Black Walnut - Juglans nigra - Companion Plants
Black Walnut (Juglans nigra) is allelopathic, which means they secrete substances poisonous to other plants. It is a great way of dealing with the competition, and can make "companion" planting problematic. Here is a list of plants that either like being near a Black Walnut, or do not mind. It is not exhaustive, but its relative shortness might give a clue as to how effective Black Walnut is at discouraging close neighbours. We do not sell any plants on the list but we hope the reference is useful.
Crocus
Eranthis hyemalis, winter aconite
Galanthus nivalis, snowdrop
Muscari botryoides, grape hyacinth
Narcissi
Scilla siberica, blue squill
Ajuga reptans, Bugle
Astilbe
Campanula latifolia
Dryopteris cristata, Crested Wood Fern
Galium odoratum, Sweet Woodruff
Geranium sanguineum, Bloody Cranesbill/Geranium
Hemerocallis, Daylily
Heuchera varieties
Hosta fortunei
Hosta marginata
Hosta undulata
Iris sibirica
Monarda didyma
Phlox paniculata
Polemonium reptans, Jacobs ladder
Primula x polyantha, Primrose
Pulmonaria, Lungwort
Sedum spectabile, Stonecrop