General fertilizers have numbers on their labels that show how much nitrogen, phosphorus and potassium is present. When the fertilizer is “balanced” the numbers will all roughly be the same—for example, 5-5-5, would be an “equal” amount of nitrogen (N), phosphorus (P) and potassium (K).
Having this “balance” of N-P-K actually isn’t a beneficial mixture for most plants because the quantity of phosphorus within the fertilizer tends to be too high. The excess phosphorus will slowly ruin your soil overtime by loading it with too much of the element with each use, throwing the soil off balance while also polluting waterways. So what should you use?
It is important to distinguish the unique necessities of your plants in terms of what, and how much, nutrients they really need. Some will need more nitrogen; others more potassium, and some may not even really benefit from adding these elements but will thrive just fine in the soil.
