If you find you need to add nutrients to your soil, you’ll have the choice of organic or inorganic, commonly called synthetic fertilizer. Inorganic fertilizer, which generally contains some minerals and synthetic chemicals, has some pluses in its favor. It is usually cheaper than organic fertilizer and it acts more quickly. However, it does nothing for the soil and in some cases actually damages the soil with its higher salt content, so be wary. Inorganic fertilizers don’t actually amend the soil, they simply feed the plant. It is kind of like a human being trying to survive on vitamin supplements and no substantial food. There have also been some recent studies that claim plants build up a resistance to inorganic fertilizers and require more and more of them to get the same results.
Organic fertilizers are plant or animal based. They release their nutrients over a period of time. You won’t get an instant fix, as you might with synthetic fertilizers, but you will get a longer, sustained feeding period with organic fertilizers. There are many good complete organic fertilizers on the market. A complete fertilizer is one that contains all three primary nutrients, nitrogen, phosphorus, and potassium.