Essential elements All plants require certain chemical elements for proper growth and appearance. Of these nutrients at least 16 are known to be essential elements . Table 2 lists the 16 known elements and the sources from which plants obtain them. All essential elements except carbon, hydrogen, and oxygen are obtained from the soil and absorbed by plant roots. If nutrient availability is inadequate in the soil, turfgrass growth and quality may be limited, and application of fertilizer is necessary to promote proper turfgras growth.
Micronutrients are as essential as the macronutrients, but are required in much smaller amounts.
The numbers indicate the percentage of each of these nutrients. The secondaries may include Ca, Mg, sulfur, Mn, Zn, Cu, Fe and Mo. Both primary and secondary elements, if present, are listed on the fertilizer label. The label also tells the materials from which the fertilizer has been made. An example of a mixed fertilizer containing several different sources of N is shown in Figure 1.