Yes, FERPLUS 4.8 can also be used preventively, especially in calcareous or alkaline soils or soils irrigated with hard water, where iron deficiency tends to appear easily. The [o,o] EDDHA iron chelate is not phytotoxic, so there is no risk of overdosing the plant: if the soil is already rich in iron, the product simply remains stable in the soil without causing damage and will only be absorbed if needed.
In the event of a slight excess, the only possible effect is a temporary increase in the iron available in the soil, which neither harms the plant's health nor alters the pH. For this reason FERPLUS 4.8 is considered safe even as a seasonal preventive treatment.