I have a large Black Walnut Tree (Juglans nigra) in my front yard. And although I let the squirrels enjoy the nuts, I enjoy the shade that it gives. However, I do struggle with growing flowers in my front yard. Gardening near a black walnut tree presents a unique challenge due to a natural chemical it produces called juglone. This compound, released through the tree’s roots, leaves, and hulls, can inhibit the growth of many plants, causing wilting, stunted growth, or even death. With this being the only mature tree in my yard, I have researched and found ways around the juglone problem and found plants that are suited for our zone 7 climate and juglone-tolerant.

Fortunately, several ornamental flowers have shown a strong tolerance to juglone and are well-suited for the region’s temperate conditions. Among the most reliable choices are daylilies (Hemerocallis spp.), which are hardy perennials known for their ability to thrive in poor soils and partial shade. Bee balm (Monarda didyma), a native wildflower that attracts pollinators and adds vibrant red or purple blooms, is another excellent option. It’s both juglone-tolerant and well-adapted to the region’s moist soils and fluctuating temperatures.

Hostas, although commonly grown for their foliage, also produce delicate flower spikes and are tolerant of the chemical effects of black walnut. They do well in the filtered light typically found under walnut canopies. Virginia bluebells (Mertensia virginica) and bleeding hearts (Dicentra spectabilis) provide early spring color and are native to eastern woodlands, making them compatible with the natural setting of the Appalachian foothills. Irises are an old-fashioned flower that does well around black walnuts and will spread, filling up the garden bed.

For late-season interest, autumn joy sedum (Hylotelephium 'Herbstfreude') and coneflowers (Echinacea spp.) offer visual appeal and resilience. These perennials tolerate drought, clay soils, and juglone, making them a solid choice for tough garden spots. Coral bells (Heuchera spp.), with their colorful foliage and delicate blooms, also fare well under black walnuts and bring year-round interest to shaded garden beds.

When gardening near black walnuts, it’s best to avoid heavy soil disturbance around the tree's roots and to regularly clear fallen leaves and hulls that may intensify juglone buildup. Creating slightly raised beds or amending the soil with compost can also improve plant performance. By selecting the right plants and maintaining soil health, gardeners can create a vibrant and enduring flower garden, even in the shadow of a black walnut tree.

You can find many of the plants that grow near a black walnut at the Clay County Master Gardener Plant Sale, May 2-3. For more info, visit clay.ces.ncsu.edu or call our office at (828) 389-6305.