A Cardinal number represents an equivalence class of sets between which there is a bijection (one-to-one correspondence). It is the number of elements in any member of the equivalence class. An Ordinal number represents an equivalence class of well-ordered sets between which there is an order-preserving bijection. It is the number of elements in any member of the equivalence class. The difference is only in whether the sets are ordered.
Phosphorous aids in the transfer of energy from one part of the plant to another and is responsible for strong root growth and healthy, hearty blooms. If you need to revitalize a blooming plant, a plant that isn't producing as much fruit as it should or a sparse lawn, a phosphorous rich fertilizer is the best choice.
Seed germinates best when it is either drilled or buried to a depth of about three quarters of an inch. While not quite as much of a fertilizer user as corn, sorghum does like its nitrogen. Without the aid of a soil test, fertilize at planting time with 300 pounds of 19-19-19 per acre.