Growing in lightly fertilised biological soil means growing in 100% natural soil, a well-aired medium without disease organisms. Atami was able to reach an air content in the Bio-soil substrate of 25% without using perlite. The lightly fertilised soil contains starter nutrients to enable plants to immediately begin their exuberant growth. After the successful start, Atami advises to re-fertilise the plants with liquid fertiliser for an optimal result.