sunflower

Does anyone know whats going on with these sunflowers leaves? I have planted tons of sunflowers all over but in this section a few plants have this happening.

When do you cut the head of the sunflower for seeds? The sunflower is not dead yet but the flowers itself is rotting and soft in some spots of it. I did see the seeds are in there. I am new to sunflowers and was wanting to save seeds for next year and eat some as well. But not sure if it’s...

Does anyone know of a database that contains sunflowers .I want open pollinated sunflowers so I can keep the seeds but it can be very difficult to tell if the sunflower is a hybrid or not. I only have one sunflower in mind right now (dwarf incredible ) but I am going to be growing a few other...