Yesterday afternoon, I went out and removed the very worst white one, there is one behind that which is huge anyway. I had a clump growing all together, so I dug them all out and moved the largest across to another bed. It was raining so I hope it settles in. There are lots of little plants around. So I don't think I will run out.
It is difficult to see the soil, because of the millions of Marigold seedlings. At least I think that is what they are !!! Thanks for your replies, Mrs B