Peat-based soil with coco to air it up. Peat, coco, perlite, and pumice base. Formula 707 has less perlite and more peat than the Original Potting Soil, which means that Formula 707 holds water slightly longer, but you can start feeding it a little faster. Begin feeding your plants 10 to 14 days after transplanting for vigorous fruiting and flowering plants.Â