I was visiting a garden on Wednesday, and photographed a few plants that
I did not recognise. In several cases I don't know whether they're
cultivated or wild, but they're sufficiently obscure to make the former
plausible. Any ideas?

1) a meadow rue (Thalictum) - I'd like a second opinion on the species,
as I've been relying on labels in the past.

http://www.flickr.com/photos/27317581@N06/3663596304/
http://www.flickr.com/photos/27317581@N06/3663596032/
http://www.flickr.com/photos/27317581@N06/3663596482/

2) looks like an avens (Geum) to me, but I don't recognise the species.

http://www.flickr.com/photos/27317581@N06/3663573908/
http://www.flickr.com/photos/27317581@N06/3663573516/
http://www.flickr.com/photos/27317581@N06/3663573656/

3) no idea, other than that it's a dicot. Ignore the little white
flowers - they belong to bitter cresses. The pearlwort in the bottom
left gives some scale.

http://www.flickr.com/photos/27317581@N06/3663573424/

4) looks like a giant white-flowered buttercup (Ranunculus platanifolius
would be my best guess, but it's out of my knowledge of the genus). I
couldn't get close because it was 5 feet behind a fence which was
blocking off an area for safety reasons.

http://www.flickr.com/photos/27317581@N06/3662770353/

There were also several other unusual, and possibly wild plants, present
- New Zealand willow herb (Epilobium brunnescens), pirri-pirri burr
(Acaena nova-zealandiae) and hairy St. John's wort (Hypericum hirsutum).
I'm still thinking about the speedwells that I saw.
--
Stewart Robert Hinsley