All SBS composts are thoroughly composted and heat sterilized through a natural aerobic process. When a material has been thoroughly composted it becomes alkaline from the composting process. Likewise the Metroplex soil naturally has an elevated (alkaline) pH level. The pH Balanced Compost products receive additional processing so that when tilled into the Metroplex soil they will help balance the pH of the targeted areas. In addition, the pH Balanced Compost also has a very rich cotton burr base, and therefore has higher levels of nutrients available to the plants.