The Benefits and Drawbacks of Commercial Garden Fertilizers The Benefits and Drawbacks of Commercial Garden Fertilizers
Many of the problems with poor-quality garden soil, including pH imbalances and a lack of nutrients, can be remedied by mixing composted soil into it. This can be a very slow method, however, owing to the length of time it takes for organic materials to be broken down.
Fertilizers offer an instant solution to this dilemma. But whereas composted soil is made up of a rich range of ingredients - and thus offers nourishment from a wide variety of sources - many fertilizers are formulated strictly around only three nutrients: nitrogen, phosphorus and potassium. Treating gardens to a single type of fertilizer, then, is much like restricting animals and humans to a steady diet of three foods, which is hardly an ideal recipe for well-balanced nutrition.
One way to compensate for this deficiency is to alternate between different kinds of fertilizers. We might begin with one that is fish-based, for example, and then use blood meal before the next cycle and bone meal after that. Rotating our soil supplements in this was will maximize the amount of nourishing nutrients that our plants will have access to. We should be careful not to use lawn fertilizers, which have a much higher concentration of nitrogen, but rather fertilizers created specifically for garden plants. These will typically contain a balance of phosphorus and potassium and a lesser percentage of nitrogen - for example, an NPK rating of 5-10-10.
Granular fertilizers, because of their hard composition, can feed the growth of fungus when not well mixed and thereby contribute to plant diseases. Liquid concentrated varieties tend to work better, and they are also easier and cleaner to apply. Manure is ideal, because its nutrient composition is comparable to that of composted soil.
Though they may be more expensive in the short term, organic fertilizers (in whatever form) offer many advantages. They are richer and denser than synthetic varieties, which means that they don't have to be applied as often to get the same results. Also, they are kind to life forms that are beneficial to our garden soils, like earthworms. Organic fertilizers, for these reasons, can be the best alternative to compost for replenishing our gardens.