Sunflowers are an early crop, from planting to bloom, it will take from 50 to 80 days depending on the variety. For example, ProCut sunflower will bloom in about 50 to 60 days.
Plant them when all danger of frost has passed, and the soil has warmed up. Plant them in loose and well-draining soil, and in a very sunny spot, as they will need at least 6 hours of full sun.
Plant them about 1/2 inch deep and water. They will germinate in about 7 to 10 days. Remember to keep the soil wet until the seeds germinate. This is very important, because if the seeds get wet a then dry, they will not germinate.
Remember, the closer together you plant them, the smaller the flower will be. If you give them all the room they want, they will grow BIG!