Planting Depth
Planting depth is how far down in the soil you place a seed before it grows.
Think of it this way
When you drop a marble into a jar of sand, it sinks to a specific depth and stays there. A marble pushed in just a little sits near the top. A marble pushed in deeper stays down near the bottom. Planting depth works the same way — the seed stays at whatever level you place it in the soil.
Explaining planting depth by grade level
When you plant a bean seed, you push it down into the soil. If you put it too deep, the tiny shoot has to push a long way up. If it is too close to the top, it may dry out. The right depth helps the seed sprout best.