Is there a white knapweed?

[Margaret]

Tristan, thank you for the useful suggestions. I love Scabiosa ochroleuca and think I already have a plant (with lots of seed!) on the allotment - photo attached for confirmation.  I can't collect seed of the white knapweed just now because it's indistinguishable from the others at this time of year. I need to mark it next summer.

Mark, I can send you a bit of the white knapweed next autumn if you would like it. Afraid it is very vigorous and may not be good company for your choice plants. Photo shows the knapweed two days ago in Scotland.

Margaret

[Alan_b]

Also saw lots of white rosebay willow herb on the roadsides in England. I'd give that plant a home

This is grown as a garden cultivar and was a feature of the White Garden at Sissinghurst last time I was there.  I have some that grows in my lawn but only to a few inches high and never with flowers.  So although it may be a terrible weed when it is happily established, it is perfectly possible to keep it miserable.  Therefore perhaps there is some compromise set of growth conditions that would allow it to flower without spreading too fast?

[Tristan_He]

I think i mentioned the butterflies like Scabiosa - here is the evidence!

Tristan