The Use of Biochar in Growing Citrus

The Use of Biochar in Growing Citrus

Biochar holds a lot of promise for improving soil health in Florida’s citrus industry, especially when it comes to combating citrus greening. Citrus greening damages a citrus tree’s roots, making water and nutrient uptake a real problem. Citrus researchers and growers have found that adequate irrigation, the use of precision fertilization, and focusing on soil health can help. This is where biochars can come in to play by improving soil health.

Present day biochars are a mirror image of Terra Preta, an ancient soil derived from organic materials rich in carbon found as deposits in the soil. These deposits are usually formed by natural forest fires and historical cultural practices like the “slash-and-burn” agricultural methods that were common in the past. Also referred to as black carbon, there are many different forms of charcoals and biochars, depending upon what the original materials were. For instance, charcoal and biochar can be made from the burning of wood.

Biochars have been found to have many uses, such as minimizing gas emissions, absorbing carbon from the air, reducing leaching of nutrients to groundwater, and reducing contaminants in soils. Biochar has also been found to be an impressive soil amendment as it increases soil fertility and productivity. It is commonly used to reverse deforestation because the biochar increases biodiversity in the soil by creating spaces for soil microbes to reside. Biochar helps build structure in the soil and is described as a fixed carbon that can  remain in the soil for over 600 years. A softwood-sourced activated biochar can have over 550 acres of surface area in one cubic foot (6 gallons).

Biochar can also be made through a process called pyrolysis. Pyrolysis is a process where biomass materials are heated at extremely high temperatures in limited- or zero-oxygen environment.

Improving soil health has been shown to aid citrus greening- infected citrus trees, and biochars may be one of the best options for amending the sandy soils of Florida’s citrus groves as they retain water, applied fertilizer and nutrients. Research is currently ongoing by UF/IFAS researchers and gaining popularity with growers into biochar’s uses in an array of agricultural crops.