What is soil made of?

The three main soil particles are sand, silt, and clay. Different soil types are formed based on the mixtures of these three main soil particles, organic matter, and other substances.

Sand is the largest particle size. It is dry and gritty to the touch. It does not hold water as well as other soil types.

Clay is the smallest soil particle size. It is sticky to touch when wet and smooth when it is dry. It retains water much longer than sand or silt.

Soil is organized into layers, or horizons, based on the material of that layer. The furthest layer down is bedrock, which is a layer of solid, hard rock. Above that layer is parent material, composed of bedrock that has started braking apart due to earth's forces. Above the parent material is the subsoil layer, composed of parent material that is even further broken apart into smaller pieces. The topsoil continues to be broken down due to erosion from things like wind and water and is where plant roots begin to take hold. The top-most layer is the humus layer comprised of both live and decomposing organic material.

Climate and terrain play a huge role in the type of soil found in different areas. The climate and terrain are going to determine what plants, animals, and microorganisms are able to survive, along with the type of weather that will be experienced in that area. All of this plays a role in the health, movement, and weathering of soils. There will also be varying amounts of sand, silt, and clay mixtures for different types of soils.

Healthy soil is soil that is able to sustain plants. Healthy soil will have good structure and texture, allowing water and air to move through it. It will also have nutrients, like nitrogen, phosphorus, and potassium, that are beneficial for plant growth. Microorganisms like bacteria and fungi, along with other insects and worms, will be present and play a large role in breaking down organic matter and releasing more nutrients into the soil.

Farmers practice conservation tilling, plant cover crops, practice crop rotation, use buffer strips, and utilize technology to ensure their soil is healthy. Every farm is different, so farmers have to figure out what works best in their location for the specific crops they are growing.

There are many nutrients found in the soil that are beneficial for plants, but the main three are nitrogen, phosphorus, and potassium.

Nutrients in the soil can be depleted for many reasons, so farmers use fertilizer to add those nutrients back to those areas.  Farmers choose the right nutrients for the plant's needs, choose the right time during the plant's growth to spray, spray only in the areas that need additional nutrients, and spray only the right amount needed for their plants.

Soil is made up of soil particles (sand, silt, and clay) along with organic matter, minerals, water, air, and countless organisms like bacteria, fungi, insects, and worms.