I have a sunny area that is suited for vegetable and flower gardens, but it is surrounded on two sides by walnut trees. Last year nothing did well at all. Are the walnut trees detrimental to growing other things?
Black walnut trees produce a substance that can inhibit the growth of other plants. Usually the effect of this substance is within the drip line of the tree, but leaves and other tree parts that fall on your garden could be hurting the growth of your plants.