Huckleberry bushes and English Walnut

Asked May 28, 2020, 1:57 PM EDT

Hi there! My property has 2 large Old (100+ YO) English walnut trees on it. We are currently working on planting some understory plants including non invasive buddlea and Paw Paw trees. We have a huckleberry Bush from a nursery I am also hoping to plant somewhere shaded, ideally under those walnut trees. I know blueberries don’t do well with juglone and some rhododendrons, but I’m also not certain how much juglone is put off from an English walnut due to most of the available information being about black walnut. Any guidance you could provide about how to plant this huckleberry and any other understory shrubs you might recommend would be greatly appreciated!

Columbia County Oregon

1 Response

English (aka Persian walnuts) do put out some juglone through their leaves when they drop. In addition, almost all English walnuts are grafted onto black walnut rootstocks which do affect the root growth of a number of species within their root zone. I don't know about Paw Paws and their resistance to it. They did evolve in the same place as black walnuts but don't know if that makes any difference. Also not sure about Buddlea. The list of plants that play well with black walnuts is small but probably not completely investigated. Often shade cast by the trees is enough to reduce the number of plants that do well underneath. But a tall 100 year-old tree could provide more light. hope this helps. Call me at 503 841-2200 if you want to visit more. Chip Chip Bubl OSU Extension/Columbia County. chip.bubl@oregonstate.edu