About Mag-I-Cal Plus Soil Food for Lawns in Alkaline & Hard Soils (11357): Lawns thrive in soil with pH levels between 6.2 and 7.0. When soil pH is above this range grass becomes light green, weeds persist, and fertilizer nutrients aren't fully absorbed. Mag-I-Cal Plus rapidly and efficiently lowers soil pH in alkaline soils. Our soil amendment helps break up clay and compacted soils. This improves root penetration and promotes growth by increasing biological activity and releasing nutrients trapped in the soil. It also increases the ability of your grass to utilize nutrients in the soil. Lawn fertilizer is wasted when soil pH is not balanced. When the soil chemistry is balanced, the nutrients are able to be absorbed. About Jonathan Green: We're a supplier of grass seed, soil enhancers, fertilizer, and other lawn care products. If you want a great-looking carefree lawn, we can help you achieve success. Our family has been growing great-looking lawns for six generations. We want to give you a thick and healthy lawn to help ward off problems before they start.