*Where soil pH is '''higher'' than the design/product specification or Acceptance Criteria ranges, corrective action involves amending the soil with sulphur or [[compost]] to lower the pH back to neutrality. Amendments to [[green roof media]] should be prescribed by the designer, product vendor or media supplier. | *Where soil pH is '''higher'' than the design/product specification or Acceptance Criteria ranges, corrective action involves amending the soil with sulphur or [[compost]] to lower the pH back to neutrality. Amendments to [[green roof media]] should be prescribed by the designer, product vendor or media supplier. |