My grandkids and I planted some sunflower garden seeds this summer and all we ended up with is BEES.  Thousands of bees and wasps, but so far no nests that I can find.  A couple of years ago I had a bird feeder out in the back yard and I bought some bird seed mixes containing sunflower seeds and they grew clear up to the top of my deck which is at least 25 feet!  Amazing.  You order specific, expensive "garden seeds" and they don't grow but wild seeds grow like mad, imagine that.