Planting Under Black Walnut Trees

We’re often asked about planting under Black Walnut trees. Black Walnut trees can be difficult to garden around as the tree roots exude the toxin Juglone, which permeates the soil and prevents many plants from growing under the tree and even beyond the drip line.

Question: Is the New Jersey Tea plant Black Walnut tolerant?
Answer: According to several sources, New Jersey Tea (Ceanothus americanus) is not resistant to Black Walnut. You can confirm this on Michigan State University’s Extension website.  There are many native plants that will grow under and around Black Walnuts. Here are some of our favorites:

Arisaema triphyllum (Jack-in-the-Pulpit)
Asarum virginicum (Wild Ginger)
Aster sp. (Aster)
Carex sp. (Sedges)
Caulophyllum thalictroides (Blue Cohosh)
Dicentra cucullaria (Dutchman’s Breeches)
Geranium maculatum (Wild Geranium)
Iris versicolor (Blue Flag Iris)
Lobelia siphilitica (Great Lobelia)
Monarda fistulosa (Wild Bergamot)
Podophyllum peltatum (Mayapple)
Phlox divaricata (Wild Blue Phlox)
Polimonium reptans (Jacob’s Ladder)
Sedum ternatum (Stonecrop)
Solidago spp. (Goldenrod)
Trillium spp.
Uvularia grandiflora (Bellwort)
Viola spp. (Violet)
Osmunda cinnamomea (Cinnamon Fern)
Polystichum acrostichoides (Christmas Fern)

Big Leaf Aster (Aster macrophyllus)

Big Leaf Aster (Aster macrophyllus)

Prairie Nursery’s No Mow Lawn also grows well under walnut trees:

No Mow Lawn

No Mow grass area under the walnut trees in the Prairie Nursery display garden.

 

9 Comments

  1. Tom

    I forgot bottle brush buckeye (Aesculus parviflora) does fine under black walnuts too.

  2. Tom Kessel

    Add these to your list: black haw vib., arrow wood vib, native wahoo (Euonymus atropurpureus) grey twig dogwood, and Cornus florida …. blood root, Va bluebells,
    trillium, wood poppy (Stylophorum diphyllum), may apple, jack in the pulpit, OH
    goldenrod, sky blue aster, sweet black-eyed susan, michigan lily, and spiderwort.

    It looks like many of our native plants have evolved to grow close to walnuts.

    Winterberry Holly is a no go.

  3. Kay Lowery

    I have Amsonia tabermontana growing under my walnut tree.

  4. Carlynn Brandon

    Can you use holly shrubs under walnuts?

    1. mary (Post author)

      Hi Carlynn, Yes, I have seen American Holly (Ilex opaca) listed as a Juglone tolerant shrub. Click here for a link to the source.

  5. Heather

    Great list!
    I have a large black walnut in my yard where I’ve done a woodland restoration (it was formerly lawn).
    Native shrubs doing really well: Nannyberry Viburnum, American Hazelnut
    Native perennials: Wild Columbine, Wild Geranium, Woodland Phlox, Penn Sedge, Wild Ginger, Early Meadowrue, Downy Yellow Violets, Zigzag Goldenrod

    1. mary (Post author)

      Thanks for the additions… We’ll keep growing the list!

  6. Ed

    My Dutchman’s Breeches and Blue Cohosh do just fine under my black walnut trees.

    1. mary (Post author)

      Ed, thanks for the tip. We added those species to our inventory just this year, maybe that’s why they weren’t on there. I’ll put them on the list. -mary

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