Soil Nutrient
Soil Nutrient is food in the dirt that helps plants grow strong and stay healthy.
Think of it this way
Dissolve a spoonful of plant food in a glass of water and watch it fade into the liquid. Plant roots draw that water up, pulling the food along with it. Soil nutrients work the same way. Nitrogen, phosphorus, and potassium dissolve into soil water and travel up into the plant.
Explaining soil nutrient by grade level
Soil has tiny bits of food in it that plants eat through their roots. You can test dirt from a farm, a forest, and a compost pile. Each type of dirt holds a different mix of plant food. Some dirt feeds plants more than others.