[ex-cavator]

Help! I'm trying to create a butterfly bed and started out with a newly created plot which included some imported soil. Most of my seeds are coming up OK but the plot seems to be over-run with this silvery leaved 'thing'. I'm sure it's nothing I want but can't find out what it is. Can anybody advise?

 

[New shoot]

It looks like annual poppies to me.  They self seed like mad, so even if you didn't plant them, the tiny seeds could have come in with the soil.

If there are too many, yank them out, but I would leave a few to see what colours you get.  Then flowers are very popular with insects 

[ex-cavator]

Thanks, New Shoot - sounds like a good call, particularly as the imported soil was from a cottage garden. I've ripped about half of them out, leaving a couple of patches. Will probably brighten things up a bit, as most of my 'butterfly plants' were going to be white / lilac / blue anyway