In the foreground of the upper left image is some Canadian Burnet, Sanguisorba canadensis , a plant, that by its name , you suspect can tolerate Zone 3. The late-blooming, cylindrical spikes of creamy-white flowers can reach a height of six feet. It can tolerate partial shade. The lower right image has some more Purple Coneflower to the right of the bench.
In the foreground is an Helichrysum petiolare, Limelight, considered an exotic plant pest in California with a potential to spread. Coming from South Africa, it can't make it in winters north (in the Northern Hemisphere) of Zone 9. Known as a Licorice Plant, it can grow to two to three feet in height. As shown, it has pale yellowish foliage. Behind it is Tibouchina urvilleana, (glory-bush, princess shrub flower). It can grow to five or ten feet, likes sun and can be used as a houseplant.
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