What’s the difference between sand and soil?

Question

I always though vegetation can’t grow on sand, but then there was this news about a mini forest pop up after the monsoon rain in Saudi Arabia.

In: 4

Answer 1

Organic material

Straight sand is just minerals and tiny rocks and contains no nutrients or the like.

Soil is a mix of sand and silt and clay and organic material (Humus) which provides nutrients to plants. Its this organic matter that gives soil its blacker color. It comes from dead and decayed plants and can bring carbon and nitrogen down into the soil for future plants.

What you see on the surface as sand may actually have a layer of soil underneath it. This is one of the tricks with mulch, you need a thick enough layer that anything trying to grow upwards through it dies before it breaches the surface. If the layer of sand over the soil isn’t super thick then you’ll end up with plants that seem to be growing in normal sand.