I used to spray rock mulch for weed control. Weeds always came back, very quickly. Either it ends up in ground water or it breaks down into other compounds. It does not keep killing plants for a long time.
It depends on the weeds and the time of year. But figure 1 established weed can block light, moisture and warmth from reaching many seeds. Take out the growing weed, and many seeds can start receiving the resources they need to grow.
I used to spray rock mulch for weed control. Weeds always came back, very quickly. Either it ends up in ground water or it breaks down into other compounds. It does not keep killing plants for a long time.
I've noticed that the weeds seem to come back worse than before. I wonder if that was a "design feature?"
It depends on the weeds and the time of year. But figure 1 established weed can block light, moisture and warmth from reaching many seeds. Take out the growing weed, and many seeds can start receiving the resources they need to grow.