20+ Holly Bush Leaves Turning Brown. As the winter passed (chicago), i noticed the leaves on one of the older bushes began to turn brown and fall off. They have been doing well, until just the last week or two, when one of them has developed a large brown patch of dead leaves.
Large brown splotches on the leaves, especially around the edges, can be a sign that your holly plant has sustained weather damage, such as a sudden cold snap or a prolonged dry if left untreated, the spots will spread and darken until they turn black.
These types of deficiencies drastically slow down plant growth and can diminish harvests significantly. This most often happens from the bottom up, but it might also start on outer leaves on bushier plants. My holly bush that was brought from my previous garden is losing leaves that have turned brown, i have fed it with growmore and kept it well watered. Homeguides.sfgate.com > garden > pest control fungal diseases.