We have a mixed privet and other plants in our hedge. Section near a black walnut tree in neighbour’s garden has died.
What should we replant?
Thank you for contacting Toronto Master Gardeners with your question about a hedge to plant near a black walnut tree.
The black walnut produces a chemical called juglone that may be toxic to certain plants.
The Morton Arboretum has information on plants that may be grown near Black Walnut trees. They include a special note about juglone and toxicity: Note that black walnut toxicity due to juglone has not been studied in depth. Much of what is known is based on one study done many decades ago. This means that any list regarding this topic is incomplete and some of the information may be anecdotal.
This means that you will need to trial some plants and see if they can get established. Assuming you want to plant where the wooden fencing is shown, you might consider either an Eastern Red Cedar (Juniperus virginiana) or an Eastern White Cedar (Thuja occidentalis), or any other Arborvitae (Thuja spp.) species. Other deciduous plants that may grow there include Rose of Sharon(Hibiscus syriacus), Ninebark (Physocarpus opulifolius ), or New Jersey Tea (Ceanothus americanus). When planting in the indicated location it is important to provide adequate water during the first summer and well into the fall before the first frost to establish a healthy root system. Mulch to prevent evaporation and weed growth would also be helpful.
Good luck with your plant choice.
July 2, 2024