Regular deep irrigation encourages stronger plants and deeper root systems. Such plants will be less apt to need staking. Mulching will help keep down weeds and conserve water. Sunflowers are somewhat drought tolerant, but flowers and seed production are better with adequate watering. No fertilizer necessary in good garden soil.
Sunflowers grown in home gardens generally have few if any pest or disease problems.
Remember sunflowers like the summer heat. Our planting here was done on May 3rd. We sowed the seeds directly in the soil. The blossoms generally face east. Keep that in mind when choosing a planting location.