Proper SOP Application in Almonds

Potassium plays a critical role in maintaining healthy, consistent almond yields from year to year. But equally important is ensuring proper application rates, methods and placement to promote the optimal uptake of nutrients trees need to reach their full potential. Use the following best practices as a guide to help you get the most out of your potassium application.

Application Rates

Almond trees can remove as much as 55 pounds of potassium from the soil per 1,000 pounds of nuts produced1—making it essential to replenish critical potassium lost every year at harvest. Leaf sampling in July should be used as an indication of potassium levels, with the goal of attaining and maintaining optimum leaf concentrations of potassium. Typical potash application rates range from 150 to 250 K2O pounds per acre, just to replenish the potash removed at harvest.

Application Methods

Potassium can be applied in granular form through banding or directed broadcasting in the sprinkler wetted area. It can also be applied in liquid form through an irrigation system. A granular application of SOP in the fall is ideal for recharging potassium depleted soils and making nutrients readily available for the growing season. Dry application also helps to maintain valuable soil reserves that liquid-only applications may not preserve.

In some cases, a liquid potassium application can be used to supplement deficient soils throughout the growing season. However, it’s important to note that some liquid sources of potassium come at a premium price and can even lead to plant toxicity and reduced yields when over-applied. When supplemental potassium is needed, consider an in-season application of dry SOP, or a soluble or liquid form of SOP which tend to be less expensive and safer alternatives to most other liquid forms of potassium.

Proper Placement

When applying granular SOP, proper placement is one of the most important factors in ensuring its effectiveness. Place SOP as close as possible to the water source and root system for the optimal uptake of nutrients necessary for achieving healthy, consistent yields. Proper SOP application should be determined based on your irrigation practices: