Fertilizers are much to plants what vitamins are to humans; they provide supplemental nutrients and minerals that plants might not otherwise obtain due to inadequate soils or scarcity of resources. Fertilizers may be organic or synthetic and used in commercial and residential settings. They contain nutrients and minerals used by most plants and flowers, and consumers may purchase fertilizers formulated to promote the growth of specific species.
Fertilizers are most effective at helping plants thrive and survive when their natural conditions are subpar. If plants and flowers are placed in rocky and nutrient-deficient soils, certain essential minerals and nutrients may be lacking from their diets. Fertilizers help only when nutrients are nonexistent; if added to already rich and fertile soils, they can actually impede plant growth. Most fertilizers release nutrients in timed increments. This enables plants to grow at steady and predictable rates, which is often desired by farmers and commercial greenhouse owners who strive to produce uniform crops and flowers. The timed release of fertilizers is quite different from the natural mineral absorption method of plants. Left alone, they soak up water and nutrients when available and convert most vitamins into instant energy, which comes in the form of glucose. Some fertilizers also contain salt, which helps plants absorb and retain more water and nutrients.