Q.Recommend very hardy perennials
I’m looking for some very hardy perennials which can grow in demanding conditions. In winter, often -12C and quite wet for long periods, and in summer, 38-40C and very dry. Unlike everyone around us who have poor soil and grow plants for hot, dry conditions, we are in the bottom of a valley on good, alluvium soil, but the cold/wet kills most plants. The other constraint is I don’t want any yellow or orange plants!
Here are some links that will help you make some selections.
https://www.gardeningknowhow.com/ornamental/flowers/fgen/plants-for-cold-regions.htm
https://www.gardeningknowhow.com/ornamental/vines/ovgen/growing-perennial-vines.htm
http://www.extension.umn.edu/garden/yard-garden/landscaping/best-plants-for-tough-sites/docs/08464-complete.pdf
