In article , K
writes

It seems to be a biennial, tends to die after flowering, but the seeds
will give plants that flower in the second year. So look out this year
for last year's seedlings to give you flowers next year. Mine only grow
to about 4ft.

Mine self sowed themselves into my red border and grew to about 7ft!
Today I yanked them out as one had been pushed over for some reason and
the other was squeezing out some salvias!
I also have a self sown hollyhock that is flowering in all its awful
Barbara cartland pink at about 8 and a half foot high! Didn't even get
blown over in the wind!

Janet

--
Janet Tweedy
Dalmatian Telegraph
http://www.lancedal.demon.co.uk