Humicacid Chart Note: John & Bob's Soil Optimizer consists of the concentrated humus used for this study along with three other organic ingredients to maximize benefits by blending calcium, iron, and soluble concentrated humus. Root development was greater in creeping bentgrass treated with concentrated humus at Virginia Tech. Four weeks after a foliar application of concentrated humus solution at 7.5 grams per 100 square meters per month. Concentrated humus enhances root growth through a hormone like response by reducing the activity of the plant enzyme IAA (auxin) oxidase. Hence, roots elongate faster. More root initials are also produced.