The Sustainable Farming Incentive (SFI) scheme offers £45 per hectare to those willing to adopt its rules for three years. Among the rules are strict restrictions on the use of chemical insecticides, seed dressings, nemacides, acaricides and silica insecticides. However, this has caused some confusion with farms using silicon biostimulants.

“The SFI guidelines clearly state that the use of silica insecticides is prohibited. However, silicon biostimulants are allowed under the scheme and are fundamentally different in the way they work,” says agronomist Mike Stoker, from silicon specialist Orion Future Technologies.

He suggests greater clarity is needed to help farmers differentiate between silica insecticides and products that make silicon plant-available using monosilicic acid.

“Silica is a common alternative to chemical insecticides. However, it is not permitted under the SFI scheme. However, the use of silicon biostimulants that make silicon plant-available and have the potential to alleviate abiotic stresses such as drought, salinity and heavy metal toxicity can still be used,” says Mr Stoker.

The use of silicon biostimulants also has the potential to increase yield by improving the plant’s ability to absorb not just silicon, but other nutrients from the soil.

“Helping plants to absorb more silicon strengthens the cell walls of the plant and helps root growth which can lead to higher yields. However, the plant is also able to absorb other nutrients such as boron, calcium and iron, which also help improve resilience against common stresses,” he adds.

With the drought conditions experienced this year, and the threat of pests increased by a mild autumn, SFI land is likely to be under greater pressure.

“Aphids and CSFB are a threat this autumn, so using silicon products will help establishing plants to thicken cells walls and increase leaf hair density to discourage biting pests. With the ground still very dry in some parts, the use of silicon can help plants to grow deeper- seeking roots faster, which will help the plant find moisture,” says Mr Stoker.

However, he stresses the need to find products that are permitted under SFI regulations.

“There is confusion over the use of silica pesticides and silicon biostimulants. Silica must not be used on SFI, but silicon biostimulants can be used as a biological way to strengthen plants against environmental pressures,” he concludes.