Organic vs Synthetic
Synthetic fertilizers deliver nutrients in a form plants can take up immediately, which makes them fast and predictable but easy to overapply, and they do nothing for soil life. Organic fertilizers - compost, blood meal, bone meal, fish emulsion - release nutrients slowly as soil microbes break them down, feeding the soil as well as the plant. For a home garden, compost plus a mild organic fertilizer covers most needs, with a synthetic feed reserved for correcting a visible deficiency quickly.