By Kirstee Schutte, Nebraska Extension Master Gardener
Soil fertility is the ability of a soil to supply nutrients to a crop. Having the ability to have the right amount of nutrients available at the right time is critical to plant productivity, but you can have all those nutrients available but not the right conditions for the plant to uptake them. An often overlooked component of soil fertility is the cation exchange capacity which is a measure of the total negative charges within the soil that absorbs plant nutrient cations. It is a measure of the soil’s ability to retain applied nutrients, specifically positively charged nutrients called cations.