By Baffledbill
Lanarkshire,
United Kingdom 
My 6 years old grandson brought me home a sunflower from school in June to look after for him, it was about a foot high and since planting it in the garden it's thrived appeared very healthy and just grew and grew. Suddenly though it seems to have died, can anyone explain why this may have happened in such a short period of time?
I have included two photographs, one which was taken just last week, the other from this week.
9 Sep, 2015
Answers
could the neighbours behind have dug some of the root out. failing that I'd go water shortage and the sudden cooling in temps on a night too.
9 Sep, 2015
Sunflowers are annuals. It grew, it flowered, and now it has finished it purpose in its life. Save the seeds and have your grandson plant another sunflower next year. Only I think that next time that young man will have grown taller than the sunflower.
10 Sep, 2015
Yes, you're right Loostrife but they are still going strong at the moment in the UK and shouldn't die back for another month or so, not like Baffledbill's flower.
10 Sep, 2015
Thanks to everyone for your comments, very helpful. The flower head is about the size of a 10 pence piece, will I get seeds from this?
10 Sep, 2015
You may be lucky. I've had some growing from the spilled seed in the bird feeder and they are really strong.
10 Sep, 2015
It looks like lack of water, especially as it was doing so well after you planted it.
9 Sep, 2015