Zone 3 hardy clematis
I am going to the MSSM (Maine School of Mathematics and Science) theat is up in Limestone where there used to be an old huge airforce base durring the Cold War. B-52's werepresent for long range bomb missions to Europe if necessary. Anyway its really cold up there and its a zone 3 also the growing season starts late April to mid May, and ends in mid September (Active growth anyway.) I need a very hardy large flowered hybrid some places say they are hardy but conformation of specific species known to grow would be great. And any other very colorful hardy plants are highly desireable to me the school has no landscaping and to me that is depressing so any help would be great.