Phlox paniculata ‘Delilah’ – Probably the most intense violet-purple flowers you are ever going to find in this species and it does not readily fade. The blooms are quite large given the plant size and it is also quite mildew resistant. This compact cultivar works well in containers or in the mixed perennial border. Grows 24″ high by 18 to 24″ wide. Hardy to zone 4.
Physotegia virginiana ‘Pink Manners’ – A newly introduced clump-forming Obedient Plant with spikes of pale pink flowers borne from mid to late summer. It is a companion plant to the white-flowered ‘Miss Manners’, both of which were bred by Darrell Probst. ‘Pink Manners’ also has strong stems that do not require staking. Grows 36″ high by 20″ wide. Hardy to zone 4.
Solidago LITTLE LEMON (syn. ‘Dansolitlem’) – This is probably the most compact Goldenrod available on the market today and the tiny lemon yellow blooms are borne in large terminal inflorescences from mid to late summer, with some repeat flowering when deadheaded. Great in combination with Blue Spirea (Caryopteris). Grows 14″ high by 18″ wide. Zone 4.
Buddleia davidii ‘Royal Red’ (syn. Buddleja) – One of the standard sized Butterfly Bushes with highly fragrant reddish-purple elongated flowers that average 6-12″ long. These are produced in late summer when any colour in the garden is much appreciated. Deadhead to promote more flowers and hard prune in spring. Grows 6-10′ high and wide. Hardy to zone 5.
Sedum spurium ‘Dragon’s Blood’ (syn. ‘Schorbuser Blut’) – An herbaceous Sedum which forms a low carpet of green to red tinted succulent spoon-shaped leaves. These are absolutely smothered in summer with brilliant ruby red star-shaped blooms held on short-stemmed clusters. This rampant spreader tolerates drought quite well. Grows 3-4″ high by 18″ wide Zone 3.