Thalictrum (Meadow Rue) adds a lovely light and airy feel to a border. Last year I saved lots of seeds and planted them in Spring, not one plant resulted. Maybe they need to be sown when fresh? There were however lots of self-sown seedlings so I got my extra plants anyway!
Lysimachia or Loosestrife loves a damp area and will tolerate shade. It is however a rapid spreader so be careful where you plant it. It is propogated by division of clumps in Autumn or Spring.
In the polytunnel Antirrhinums or Snapdragons as they are commonly known continue to do provide lots of colour. They propogate themselves from year to year.
Cosmos is doing well too, I love this shade. Deadheading ensures a continuity of blooms. Towards the end of the season I will allow some seed heads to form for propogating next years flowers. Gardeners always need to think ahead.
Galega officinalis “Alba” also known as Goat’s Rue or French Lilac does well in moist but well-drained soil. It isn’t fussy about siting, I have it in full sun and also in a partially shaded spot. It does well in both situations. It can be propogated by division or seed. It is on the Noxious Weed List in parts of America because of its rapid spread, I have not found it to be such a rampant spreader here.
Shasta Daisy, another perennial which does well in our area. It has a long flowering period and it too divides well to provide extra plants. It is very hardy which is useful considering our increasingly colder Winters in Ireland.
arignagardener 
I just planted Meadow Rue this year. I hope it grows up to look like yours – beautiful!
Bridget, Thank you for your ideas for my new shade garden and also thank you for visiting my blog! I really like your blog and look forward to checking it out further! I have written down your ideas of shade plants and will investigate them further! Thank you very much! Happy Gardening! Mindy
Beautiful blooms! I especially like the cosmos…such a lovely shade of pink. And the meadow rue has such an airy quality…gorgeous!
I’ve never grow cosmos, but have fallen in love. I will definitely be spreading seeds next year! Love your snapdragons, too.
Bridget, I have Thalictrum (Meadow Rue) in my back garden. Like you I tried to plant its seeds with little success. It does seems to prefer to find its own way and self-seed. Little seedlings have popped up here and there. Unfortunately, the seedlings are willful and don’t like being relocated either. It seems it often takes patience to get to know a plant and learn its ways. It is a pretty plant though, I am determined to get to know it better.
Cosmos are such a great late summer flowers. My favourite are also the deep pink ones.
Thalictrum is a beautiful plant isn’t it, can’t get enough of it ! As you say, gardeners are always having to think ahead, so busy at the moment sewing seeds of primulas and taking loads of cuttings. Your garden is looking really lovely with lots of colour everywhere, very pretty.
Love your blog!
I’m your new follower.
Barb
I like the meadow rue and the goats rue, never seen them before, very pretty, just the sort of flowers I should have in my garden.