By Kayakgenius
United Kingdom 
This plant has grown where I planted lettuce, but it is clear now that it is not lettuce and indeed is about to produce some pink flowers.
Please can someone identify it for me?
3 Jul, 2015
Answers
Yes - definitely a poppy.
3 Jul, 2015
Many thanks for your answers. I have googled papaver and yes it appears to be that. I guess I need to move it from my salad bed and put it some where else before I get inundated with self-sown poppies!
3 Jul, 2015
Or let it grow and remove the seedheads before they ripen. Though you can collect the seeds and use them in cakes, bread etc.
3 Jul, 2015
I doubt you will be able to move it now as these have a long tap root and dislike disturbance.
4 Jul, 2015
Previous question
Looks like an opium poppy, papaver somniferum.
Seed could have been dormant for a while, just waiting for the right conditions, or fresh seed dropped by a bird.
3 Jul, 2015