What type of soil generally has the highest nutrient retention?

Clay soil is widely recognized for its high nutrient retention capacity. This is primarily due to the small size of clay particles, which results in a larger surface area available for nutrient adsorption. Clay particles possess a negative charge, allowing them to attract and hold onto positively charged ions (cations) like calcium, magnesium, and potassium, which are vital nutrients for plant growth.

The compact nature of clay also leads to lower porosity, which means that while water moves more slowly through clay, nutrients are retained within the soil better than in soils with larger particles. This makes clay particularly beneficial for retaining essential nutrients over time, supporting plant health and soil fertility.

In contrast, sandy soil has larger particles and, therefore, less surface area for nutrient retention. Silty soil, which has a medium grain size, is generally better than sandy soil in retaining nutrients, but it does not match the nutrient-holding capacity of clay soil. Loamy soil, a mix of sand, silt, and clay, also has good nutrient retention, but it is still not as effective in this regard as pure clay soil.