Recognise It?

It was a lovely morning when I got up so I headed out into the garden to get an early blip.

I have always liked the hairy lips on the fofoxgloves.

The oriental poppies are coming out and range in height from over 2' tall to this one which is maybe 2" tall.

This weed (whose name I can never remember) was snapped just before it headed for the compost heap ......... along with a load of others.
Why is it weeds can grow in such profussion in an environment that is virtually soils free?
I laid double thickness weed suppressing blanket before having 2" of river washed pebbles dumped on top.
It means no grass cutting - but very sore knees when I have to get down and pull ouyt the damned weeds that show themselves.