In the formal language of economics, X and Y are substitutes if the demand for X increases when the price of Y increases, or a positive cross elasticity of demand.
Potting mix is the material that goes into a garden pot before you put seeds and plants into it. 1  It keeps the plant in place. 2  It holds water for the plantâs roots to soak up.  It contains nutrients that feed the plant.
Add to soil to improve aeration and provide moisture retention. Can also be used for seed germination and cutting propagation or mixed with Plant Pro Potting Soil. NOP compliant, check with your certifier for use in organic production.LANT PRO POTTING SOIL*. Our exclusive organic potting mix made from sphagnum peat moss, vermiculite, sharp sand, and perlite. Enriched with Re-Vita Compost Plus 3-3-3 with kelp, humate, rock phosphate and greensand for better fertilization.