Thanks Julie - Caitlin suggested a website that sells a variety of wildflowers some would be suitable for under the trees: http://www.meadowinmygarden.co.uk/
I do intend to come down to Northampton again on my own so I can catch up with our friends we left behind.
The Monkey Puzzle is still alive but I think you said it is a slow grower. I'm afraid my own garden has been neglected quite a lot while I've been working on the Tatton garden now at the hospice. I hope it will be finished tomorrow and I will dedicate the weekend to catching up at home. Good to hear from you. Steve xx