In the Summer when it is warm.
It is best to plant sunflowers in spring so they flower for summer. With the right care and maintenance it reappears every year around the same time. Link --->> http://www.essortment.com/all/sunflowersgrow_rnfb.htm
Do you mean, can human bieings eat sunflower seeds? if so then yes. I eat them all the time
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April - June.
Nope. Just don't take them from strangers... ther IS a chance they are poisoned XD. I eat sunflower seeds all the time. And im not dead yet so...
Harvest the heads when they have dried off and allow them to further dry for a week nor two in a dry place. You can extract the seeds by rubbing the heads together to dislodge the seeds. Picking them out individually is too time consuming. Only seeds from a non-hybrid plant will grow well the next year. Also avoid seeds that seem hollow inside.
Only in some tempetures, a sunflower seed needs sun and warth a sunflower does not do well in cold cloudy areas infact a sunflower has a really big chanse of dying in cold and cloudy areas. If a sunflower is in a cold cloudy place it will die because without sunshine a sunflower can't make food without food it will starve and if it starves it will die it also needs to be warm so if you want to plant a sunflower i'd do it in the summer were it is both sunny and warm. (sunflower seeds growth) A sunflower needs to be healthy and in a good enviorment were it is sunny and warm to produce full grown and healthy seeds. In a indoor enviorment when summer it is a good time to put a sunflower i sugjest by the window were the sun is most likely to get all the sun it needs. :)
Either in Spring or Autumn when soil is moist and the temperature is mild.