Why don't sunflowers need fertilizer?

Sunflowers are relatively low-maintenance plants that can thrive in a variety of soil conditions. They have deep root systems that allow them to access nutrients and water from the soil efficiently. Additionally, sunflowers can adapt to poorer soils and often have a symbiotic relationship with soil microbes, which helps enhance nutrient availability. While fertilizer can boost growth, it's not strictly necessary for their survival and development.