Are there any special nutrients for sunflowers?

No, the sunflower (Helianthus annuus) can grow just about anywhere as long as it has full sun (at least 6hr/day), well drained soil and they like to have mulch to conserve water and increase the organic content of the soil. They do like soil with a rich organic content. Some references say sunflowers prefer a limey soil, but I've grown them for years in an acidic location and they do just fine.