Slot deposits are a type of fertilizer that contains a high concentration of phosphorous and potassium. These two elements are often combined together in a single product. Slot deposits are commonly used in commercial agriculture, but can be used in home gardens as well. Slot deposits are generally applied at planting time, but they can also be added to the soil throughout the season. Slot deposits are not recommended for use in soils that have been amended with compost or manure. slot deposit 5000