Potassium is a chemical element with symbol K (derived from Neo-Latin, kalium) and atomic number 19. It was first isolated from potash, the ashes of plants, from which its name derives.
A brief review of the macronutrients included in complete fertilizers: nitrogen (N) is involved in photosynthesis as part of the chlorophyll molecule and promotes vegetative growth; phosphorus (P) supports the transfer of energy throughout the plant for root development and flowering; and potassium (K) is an important part of plant metabolism, strengthening its overall health.
Nitrogen is a key player in producing chlorophyll; this pigment absorbs sunlight for basic photosynthesis needs. Gardeners must make sure that nitrogen, one of the three macronutrients in soil, is available for root uptake by choosing the right fertilizer. Saturating a garden with high nitrogen levels, however, does not improve plant growth. In fact, it can actually harm a garden more than leaving it to its natural elemental state. Too much nitrogen in plants is apparent both above and below the topsoil.