We planted our seeds one inch deep once the night temps started to stay around 50. (winter sowed seeds did not grow as tall and are no where near producing a flower) We spaced our seeds one foot apart. They started to sprout within 3 days of the first planting and watering. Once they grew a good six inches, we packed a little more soil and fertilizer around the base of the plants. We did this again at two foot tall to help prevent to sturdy flowers from falling over. They were also watered daily during times of no rain.
Our first bloomer is around six feet tall with a flower that is eight inches in diameter. The yellow is very bright on the petals and even with the weight of the bloom the plant is not sagging or bending over at all. These heavy feeders are doing great with a little bit of lime, magnesium, calcium and fish waste to make sure the soil keeps providing nutrients for the plants. We used this mixture every third week since the soil was very rich to begin with.
First day open
Third day open.
Sunflowers after a few weeks of growing.