Black Walnut leaves in compost

Question

Hello – I have been working on a home compost pile for the first time, adding in vegetable matter from the garden and fruit and veggie scraps from the kitchen. It’s been going for about a month and is doing well. I realized today though that one of the trees in my backyard is a black walnut tree. I have been adding leaves from a pile behind my house that is mostly red oak leaves, but it most likely has a few handfuls of walnut leaves mixed in by accident. I was hoping to use this in my vegetable garden in a few months, but I’ve read conflicting things. Will a few walnut leaves (that were already dead and dried out for a few months) mixed in to the compost ruin it for vegetable gardening? Does anyone have a similar experience? Thanks!

Answer 1

There is still debate on toxicity of walnut leaves. It was initially thought to be only in the roots but walnut roots are deep and many of the plants that won’t grow under a walnut are not in the root zone. LSU says it takes 2-4 weeks for juglone to breakdown in an aerobic compost environment. Other university extension services say not to use leaves/wood products from walnuts. Read and reach your own conclusion: https://depts.washington.edu/hortlib/resources/resource_search.php?term=10