Sunflowers are native to the Americas. As such, they grow well in most places. Sunflowers are unusual in that the flowers will track the sun across the sky. In the morning, they will face east toward the rising sun. In the evening, the flowers will face west toward the setting sun. Growing sunflowers is not difficult. Although you can successfully plant a patch by rough seeding, by planning, fertilizing, and some seed and site preparation, you can have a healthier, more cultivated looking sunflower patch.
Sunflowers need direct sun. Many varieties also grow exceptionally tall, with some varieties reaching well over 10 feet tall. If planting your sunflowers as part of a vegetable or other type of garden, plant them on the north side of the garden so they do not shade the southern parts of the garden. In the northern hemisphere, the angle of the sun is such that planting them on the south side of the garden would cause the sunflowers to shade more of the garden than on the north side.
Sunflowers grow well in a wide range of soil. Unlike other native North American plants, such as corn, sunflowers do not need as many soil nutrients and can grow very well in soils that have a lot of clay. They do, however, require soils that drain well. Sunflowers do not tolerate salty soils well.
Even though sunflowers do not need as many nutrients as other crops, they can benefit from fertilization. Initial fertilization is best before you sow your sunflower seeds. Add 3 to 4 inches of mulch and work it into the soil. Add a 5-10-5 or 4-12-4 fertilizer per manufacturer's instructions if you wish to add more nutrients to your sunflower patch.
Germinate the Seeds Before Planting
You will have better success with planting your sunflowers if you germinate the seeds inside before transplanting outside. Fold a paper towel in half once. Then fold it in half again. Mist the paper towel to make it moist. Place sunflower seeds on the paper towel about 1/2 inch apart and cover them with another damp paper towel. Mist the towels every other morning. After a week or two, your sunflowers should sprout.