What to Plant Under Walnut Trees

Walnut trees are a popular addition to many gardens and landscapes. These majestic trees provide shade, beauty, and tasty nuts. However, the large, spreading canopy of the walnut tree can also create challenges when it comes to planting under the tree. The juglone, a toxin released by the walnut tree, can kill or stunt the growth of many plants. So what can you plant under walnut trees?

Plants to Avoid

Before discussing what plants can thrive under walnut trees, let's take a look at which ones to avoid. Plants that are sensitive to juglone include many common garden plants such as tomatoes, peppers, potatoes, and blueberries. Trees and shrubs to avoid include apple, pear, cherry, and many types of conifers. Planting any of these under a walnut tree could result in failure or poor growth.

Plants that Thrive Under Walnut Trees

Although many plants are sensitive to juglone, some plants can thrive under walnut trees. Some plants that can tolerate the toxin are known as juglone-resistant species. These plants include:

Blackberry

Raspberry

Asparagus

Beans

Corn

Peas

Squash and pumpkins

Wildflowers such as columbine, goldenrod, and purple coneflower

When selecting plants for under your walnut tree, it is important to consider your location and soil conditions. Many of the plants listed above prefer well-drained soil with a neutral pH. Additionally, consider the amount of light and shade your tree provides. Some plants need full sun, while others prefer partial or full shade.

Tips for Growing Under Walnut Trees

Here are a few tips to help you successfully grow plants under your walnut tree:

Choose plants that are tolerant of juglone toxicity.

Keep plants well-watered during dry spells, as juglone is more severe in dry conditions.

Use raised beds or containers to grow plants in areas where juglone levels may be high.

Monitor plants for signs of wilting or stunted growth. If a plant is struggling, it may not be juglone-resistant and should be removed.

Maintain good soil health by adding organic matter, such as compost, to help buffer the effects of juglone.

With careful selection and management, you can create a thriving garden under your walnut tree. By planting juglone-resistant species, you can enjoy a diverse and beautiful landscape without sacrificing the beauty and benefits of your walnut tree.