How Much Mulch Do I Need—and How Much Is Too Much?

Mulch is one of the simplest tools a gardener can use to protect soil, suppress weeds, and reduce water loss. Yet it’s also one of the easiest things to get wrong. Many well-intentioned gardeners assume that if a little mulch is good, more must be better. In reality, over-mulching is the single most common mistake—and it can quietly harm plants, trees, and soil health.

Here’s how to figure out exactly how much mulch you need, when enough becomes too much, and how to avoid the problems that come from piling it on.