Friend

Looks like Ragged Robin to me and probably out of your packet of seeds , this one loves a wet damp area and the flowers loved by the bees

its Silene dioica, red campion , similar to ragged robin but ragged rob has very deeply divided petals.. it is a wild life friend but seeds freely. easy to pull out when you get too many of them.

Its a bit of a thug round here but as SBG says its easy to pull up.

We spend more time removing this than even Hairy bitter cress. It is an absolute horror of a seed weed. Get rid before it goes to seed or you will spend the rest of your life pulling them out from everywhere and I mean everywhere. We have even found it growing on our roof!

Thanks everyone. I thought as much! It has grown so quickly with all the rain we are having. Although I do believe in wildlife friendy plants I think I best get rid of this one.

at least enjoy the flowers and let the bees etc have a nectar feed. after all that's why you grew it :o)

I LOVE this red campion! Yes, it seeds itself around, but is very pretty and easy to pull out where you don't want it :)

Been pulling it out this afternoon...

Steragram-that's what I did as well.