Buddleja Monarch 'Prince Charming' is a mid-sized, long-blooming butterfly bush with huge cones of fragrant, raspberry-pink flowers.

Campanula glomerata 'Angel Bells' is a clustered bellflower with large clusters of well formed white flowers.

Campanula glomerata 'Church Bells' is a clustered bellflower with large clusters of well formed violet-blue flowers.

Echinacea Double Dipped 'Rainbow Sherbet' is a coneflower with fragrant, large, fully double, orange to pink flowers with broad, horizontal rays.

Hosta 'Echo the Sun' is a plantain lily with heart-shaped, golden yellow leaves that are corrugated with ruffled margins.

Hosta 'Seasons in the Sun' is a plantain lily with heart-shaped, golden yellow, corrugated leaves with wavy margins.

Hosta 'Voices in the Wind' is a plantain lily with wedge-shaped, variegated blue-green leaves with creamy yellow ruffled margins.

Hosta 'Wild Imagination' is a large, strap-leaved plantain lily with narrow, twisted and ruffled blue leaves and lavender flowers.

Kniphofia Pyromania 'Hot and Cold' is a red hot poker with torches of tubular flowers in bi-colours of yellow and orange.

Kniphofia Pyromania 'Solar Flair' is a red hot poker with torches of tubular flowers in brilliant yellow.

Ligularia japonica 'Tractor Seat' is a cold hardy goldenray with huge, heavily serrated and dissected leaves and yellow flowers.

Monarda Upscale 'Lavender Taffeta' is a large, mildew-resistant beebalm with fragrant lavender-purple flowers and aromatic foliage.

Delphinium Highlander 'Bolero' offers ruffly, fully double flowers in shades of lavender purple, blue, and creamy white

Hosta Shadowland 'Above the Clouds' is a large, impressive plantain lily with cloudy blue leaves that are cupped and puckered.

Hosta 'When I Dream' is a large, impressive plantain lily with tricolour variegated leaves.

Hydrangea macrophylla L.A. Dreamin' 'Lindsey Ann' blooms on new and old wood in a range of flower colours all at the same time.

Sedum Sunsparkler 'Dazzling Dynamite' has dramatically variegated leaves in shades of glowing pink, orange, yellow, and purple.

Agapanthus 'Silver Moon' has variegated leaves light lavender-blue flowers in rounded clusters.

Asarum caudatum f. album known as western wild ginger has glossy evergreen leaves and 3-petaled creamy-white flowers.

Sarracenia 'Bug Bat' is a carnivorous pitcher plant with red flowers and hoods atop tall, chartreuse-green pitchers.

Colocasia esculenta 'Waikiki' is a taro or elephant ear with stunning, shiny, variegated foliage with white and pink veins.

Grewia asiatica is a small deciduous shrub known as sherbet berry that produces sour-sweet edible purple berries.

Pandanus amaryllifolus, known as pandan or screw pine, is an evergreen tropical with fragrant leaves used in culinary dishes.

Hydrangea paniculata 'Candle Light' has large conical flower heads in creamy white that slowly age to gorgeous pinks.

Dicentra Amore 'Titanium' is a bleeding heart with pure white flowers for months on end and lacy blue-green foliage.

Artemisia 'Silver Lining' is a mounding white sagebrush with beautiful, broadly dissected, silver-gray foliage.

Echinacea Double Dipped 'Watermelon Sugar' is a coneflower with large, fragrant, fully double, deep pink flowers.

Echinacea Eye-Catcher 'Canary Feathers' is a single coneflower with large, fragrant flowers with yellow horizontal petals.

Echinacea Eye-Catcher 'Tanager' is a single coneflower with large, fragrant, orange flowers with dark cones.

Echinacea Summersong 'Firefinch' is a single coneflower with fragrant, multicoloured red and pink flowers.

Penstemon 'Midnight Masquerade' is a tall beardtongue with very dark foliage and lavender flowers with white interiors.

Hydrangea arborescens 'Candybelle Bubblegum' is a dwarf smooth hydrangea with domed white and pink umbels.

Athyrium niponicum 'Aubergine Lady' is a Japanese painted fern with green fronds maturing to deep purple-black.

Kirengeshoma palmata or Korean waxbells is a stately shade perennial with maple-like leaves and yellow bell flowers.

Agapanthus 'Valencia' offers sky blue flowers with darker veins and reverses on dark stems.

The most beautiful Hydrangea in the world? The gorgeous 'Miss Saori' won Plant of the Year at the 2014 Chelsea Garden Show.

Hydrangea paniculata 'Wim's Red' offers creamy white cones that age to pink then rich, glowing red.

Asphodeline lutea, king's spear or yellow asphodel, has tall, vertical spikesof fragrant, yellow, lily-like flowers.

'Soeur Therese' is a classy mophead hydrangea with icy white florets growing on full size plants to six feet tall.

Aloe polyphylla is a stunning, rare succulent with light green leaves arranged in a mesmerizing spiral.

'Mandela's Gold' (formerly 'Kirstenbosch Gold') is a special form of Strelitzia reginae with yellow flowers.

Actinidia deliciosa 'Jenny' is a self-fertile kiwi that produces fruit just like you find in the supermarket.

A great textural and foliage plant with cute apple green cupped flowers.

Acanthus 'Whitewater' forms vigorous mounds of variegated foliage and pink stems holding white flowers.

'Blue Heron' is a true blue, fragrant Corydalis with finely textured foliage.

Rodgersia 'Chocolate Wing' has rich, chocolate, shimmery, textured, palmate leaves -- amazing in the shade garden.

Alstroemeria 'Indian Summer' has flowers in orange, red, and yellow with luscious bronze-infused foliage. Potentially hardy to zone 5!

Perennial Hibiscus have the largest flowers in the mallow family. 'Midnight Marvel' has bold, burgundy foliage topped with huge, scarlet red flowers in summer and fall.

Convallaria 'Albostriata' is a special form of lily-of-the-valley with green leaves striped with yellow.

Kirengeshoma palmata 'Black Style' is a Korean waxbells with black stems that hold up the creamy yellow flowers.

Amsonia 'Storm Cloud' displays star-like periwinkle blue flowers above silver veined foliage on dramatic near-black stems.

Wasabia japonica is the true wasabi, not the fake stuff served in most Japanese restaurants. 'Daruma' has great vigour and flavour.

Wasabia japonica is the true wasabi, not the fake stuff served in Japanese restaurants. 'Mazuma' has great vigour and more heat.

Aruncus 'Chantilly Lace' produces lacy, branched, horizontal spikes of creamy white flowers atop Astilbe-like foliage.

Hibiscus 'Starry Starry Night' has wine purple, maple-like foliage and pink buds opening to 8-9 inch wide, pale pink flowers.

Hosta 'Sorbet' has beautifully variegated leaves and striking deep burgundy petioles, leaf bases, and flower stalks.

Rodgersia aesculifolia 'Cherry Blush' has large, palmate leaves flushed bronze and bright pink flowers.

Hemerocallis 'Voodoo Dancer' is a fragrant, reblooming daylily with double, burgundy-black flowers.

Iris pseudata 'Shiryukyo' is a tall cultivar to four feet with violet and purple tones and veining set off with a bright yellow signal.

'Dark Side of the Moon' is a unique Astilbe with dark foliage and purple flowers that bloom in late summer.