With last winter's rain, lots of horse owners are now being faced with badly poached fields. You can improve drainage by keeping ditches and drainage pipes clear. Streams should also be kept free flowing by removing debris. If your fields do not drain naturally, artificial drainage will need to be installed. Although this is expensive you will find that the ground will be able to withstand poaching and the grass will also improve.
Nutrients are naturally present in the soil and are found as either minerals or elements.
These include lime, which also contains calcium, which is needed for the formation of bones and teeth and phosphates, which includes phosphorous. Potash is a compound of potassium that is necessary for plant growth. Nitrogen is converted and absorbed by plants. A lack of nitrogen results in slow weedy growth, too much and the pasture becomes to rich for horses and is only suitable for dairy cows. You can tell quite easily if there's too much by the amount of clover growing.