By Barbarak
North Yorkshire,
United Kingdom 
I sowed pansy seeds in a seed compost but these seedlings came up first. It's possible that poppy seeds got spilt on the potting table. The stem has hairs and also under the larger leaves. Have I been nurturing nettles?
1 Aug, 2018
Answers
Ha! Ha! This happens to me when I added some to my Rose in a pot :o))
1 Aug, 2018
well one way to see if they are nettles is to brush against them and if you get stung....
they do look like nettles and I find some composts do contain a lot of them. grr
but definitely not poppies.
2 Aug, 2018
Not all nettles sting: they could be stingers or dead nettles. It looks like they're not hairy, so probably dead nettle,- but either way it's a weed!
6 Aug, 2018
there does appear to be a stinging 'hair' visible on the top left leaf stem next to the smaller pair of leaves.
6 Aug, 2018
Well, it certainly looks like it! It's not difficult to nurture nettles! They manage to insinuate themselves in anywhere! You can be sure they are not poppies at least!
1 Aug, 2018