Silicon is a beneficial plant nutrient that can increase plant strength and improve a crop’s ability to fight environmental oxidative stress. Silicon is an element that, like calcium, potassium, or zinc, is used by the plant to complete physiological processes. Similar to calcium, silicon plays a critical role in cell wall structure. Silicon and calcium uptake in conjunction has been shown to dramatically alter cell wall strength. Silicon has also been linked to phenolic compound synthesis.
Calcium and silicon nutrients in citrus offer the potential to offer several benefits. Increased calcium and silicon uptake during bloom and cell development can lead to less fruit drop. Timing is critical because calcium cannot be translocated to the fruit effectively after cell development. Applications prior to heat events can be very helpful for reducing heat and drought stress. Calcium and silicon both are phloem immobile, which would suggest that applications to the root system will be most beneficial. However, significant research has shown benefits from timely foliar applications.