I emptied my walnut leaves and husks onto the compost all autumn just to save trips to the tip: in May, with every pepper plant drooping, I understood what the heap had never broken down
A gardener’s autumn shortcut—composting walnut leaves instead of hauling them away—backfired spectacularly by May. The culprit wasn’t the leaves themselves, but the husks: a slow-decomposing reservoir of juglone, a natural toxin that cripples peppers and tomatoes. The real surprise is how easily this trap is avoided.