Owen Wormser wrote:
Scoring into a lawn using what's known as a drill seeder can help get seeds in contact with soil, increasing the odds they establish. Of course you can sprinkle seeds onto a lawn but that can be more of a crap shoot. The thing with most lawns is that they are usually comprised of cool season grasses which spread thickly, creating a carpet that can make it difficult for newly sprouted meadow plants to establish because of the initial competition of the existing grass.
I usually try to match plants to the existing environment, so in a very sandy area, I'd focus on species that truly like those conditions; unfortunately, that narrows the possibilities significantly if you're focusing on meadow plants (it's dune and desert species that usually can grow well on sand). Because the lack of organic matter and the inability of sand to hold water, growing a meadow in this type of environment can be prohibitive.