Looks like one of the willow herbs to me. Not a marigold anyway.

Agree willow herb weed, needs removing.

Oh thanks I have often wondered what this weed is in my garden

Howk it out Denise!

I think it's the one the Americans call fireweed.

Probably, do you have the Rose Bay Willow Herb around near you Beattie? Grows to a good 3 or 4 foot and seeds like mad everywhere.

Not any more, MG. We had it in a garden about 3 moves back. I used to leave a patch of it in a corner as there's some moth or butterfly, I forget the details, that lives on it.

It isn't in our garden but on waste land about 500 metres away but when the wind blows the seed...

Thanks to everyone who identified my photo as willowherb. I will remove it all right away. Could it have been in the bag of compost I used to sow my seeds in?

Unlikely but all things are possible... How long have the seeds been in the pots?

If you have pots of other seedlings that you sowed using the same compost that don't have the weed in, it wasn't in the compost.