I have a stone patio outside my back door, built with (approx.) 12"x12" pavers. Each spring, moss grows up through the cracks between the bricks. I have scraped it off and dug it out as best I could each time, but it grows back every year, sometimes even before the summer is over.
Is there a way to prevent this from growing back?
Not really, but you can use a product specifically designed for use on hard surfaces such as Patio Magic, which does have some residual deterrent effect. Use as instructed on the container. I imagine your paving is in a fairly shady area, which encourages moss and the like, particularly through winter when the air is damp. You'll likely have to use the product at least once a year.
Some people, though, allow the moss to remain, and even try to encourage its growth, considering it attractive.
