Aerated compost tea for soil biology and crop health

Aerated compost tea (ACT) is a sustainable biofertiliser and biofungicide that enhances soil biology, supporting the soil food web and improving crop health, nutrition, and resilience to pathogens and drought. It suppresses soil-borne and foliar diseases through competitive exclusion by beneficial microbes. ACT is brewed using well-aerated compost with a 50:50 fungal-to-bacterial ratio, dechlorinated water, and optional stimulants like molasses or seaweed extract over 24–48 hours. Filtering before application prevents clogging, and low-pressure spraying (≤2.5 bar) with large nozzles preserves fungal structures. Recommended application includes soil drenching after drilling and 2–3 foliar sprays during early growth (e.g. GS37–65 in cereals), typically April–June. The method is supported by the OK-Net Arable project and effective in organic and low-input arable systems. Originating in the UK (Elm Farm, Newbury) in 2017, it is backed by field and lab studies showing efficacy when high-quality compost and strict protocols are used.