So many plants are sun-loving, and walnut trees cast quite a thick shadow. However, that's not the only reason that few plants can grow with walnut trees. The fallen, decayed leaves--as well as the bark, wood and roots--create a chemical (juglone toxin) that kills many other plants. Luckily, not all plants are bothered by the this toxic substance.
Rose of Sharon
If you are looking for a colorful blooming bush that can be planted near your walnut tree, you will be pleasantly surprised by the Rose of Sharon. The blooms come in pink, purple and white. The bush grows from 4 to 10 feet, depending on the variety. This deciduous (loses its leaves in winter) plant can withstand temperatures that drop to -20 degrees Fahrenheit.
Rose of Sharon draws hummingbirds and bees, which is beneficial to other plants needing pollination in your garden. Some common varieties include: Aphrodite, Diana, Morning Star and Ardens.
There is no mistaking the begonia plant, with its dark, shiny green, bronze or dark red leaves and delicate petals. Besides not being bothered by juglone toxin, they are easy to grow, requiring little care for big rewards. They can be planted near to, or even directly under, walnut trees, as they do well with indirect sunlight.
If you live in a frost-free location, the begonia will be a perfect addition to your garden, near your walnut tree. If your home is in an area experiencing colder winters, place potted begonias beneath, or by, the tree and then bring the plants indoors during colder months. Certain Begonia types can grow to 15 to 18 inches tall and 15 inches wide. Some common varieties include: Black Beauty, Chocolate Cream, Five and Dime, Last Laugh, Kismet, Venetian Red and Vista.
Vegetables and Fruit
Yes, there are fruits and vegetables that grow very easily near walnut trees. However, they do need a full sun location for best production. Squashes, beans, melons, carrots and corn can be planted close by, giving you an excellent vegetable garden in spite of your walnut tree. Other fruit trees that are not bothered by the juglone toxin are: nectarine, peach, plum, cherry and some varieties of pear.
Some trees can be grown near walnut trees, and others should be located at least 50 feet away. Companions to walnut trees include: Eastern Redbud, Canadian Hemlock, Southern Catalpa and the Japanese Maple. Trees that should absolutely not be planted nearby are: European Alder, Silver Maple, Norway Spruce, Red Pine, Basswood, Eastern White Pine and White Birch.