Buy Byron Biochar Biochar+Frass – a complete soil condition and fertiliser product which contains millions of beneficial microbes to increase plant growth and promote the health of your soil. We have supercharged biochar by adding frass, which is produced in Australia. Frass is an all-natural fertiliser made from insect manure. It’s rich in plant nutrients and has up to two-hundred times more beneficial microbes than compost. Frass is high in chitin which activates natural plant defences against insect attack and soil-borne diseases including root rot.