(Clematis 'Jackmanii' | 📸 Clearview)
The first hybrid clematis, 'Jackmanii', was introduced 162 year ago in 1862. While the English may have acquainted the world with the "queen of vines," this genus had actually been cultivated for centuries. The Japanese used many natural selections in their gardens as early as the 17th century, including the Chinese species Clematis florida. Since then, horticulturists across the world have been quite busy, and to date, we have an estimated 1,000 cultivars to choose from.
(Clematis florida 'Sieboldii' | 📸 Clearview)
So, how do you select the right clematis for your garden? You start by asking yourself where do I want to plant it? Which is what this article is all about, providing specific clematis recommendations based on what you want this vine to accomplish in your landscape.
Clematis for Growing in Containers
Let’s start with a few parameters, that being a minimum size and depth for the containers, which is 18” x 18” x 18” (although 2’ x 2’ x 2’ is ideal). Beyond this you need to avoid metal pots, as these conduct the summer heat too readily and will literally "cook" the roots. A well-drained potting mix that still retains some moisture and adequate drain holes in the container are also considered essential. Remember that clematis like cool roots, so consider planting a few low-growing perennials at the base to shade them; several optimal choices include hardy geranium, dianthus, and even trailing Baby’s Breath (Gypsophila repens). Finally, a 3-4’ tall support system such as a metal obelisk, a narrow wood trellis or even a tripod of bamboo canes provides the horizontal lift to show-off those lovely flowers.
For specific varieties I would start with the Evison clematis, many of which are purpose-bred for container culture. A few good choices here include ‘Issey’ (cherry red), ‘Diamantina’ (pom-pom purplish-blue double), 'Sarah Elizabeth' (ruffled pink), ‘Samaritan Jo’ (silvery-pink with purple picotee) and the ever-impressive ‘Empress’ (pink bicolour double).
That being said, even ordinary varieties such as ‘Hania’ (red-pink bicolour), ‘Julka’ (purple with red vein), ‘Haku Ookan’ (deep violet semi-double) and ‘Piilu’ (semi-double mauve-pink) thrive in large enough pots.
Clematis Tree Scramblers
If you are looking for clematis to scramble up a dead tree or cover an unsightly fence or outbuilding, then you’re in luck because there are plenty of them. I would start with the montana species as they bear smaller white, pink, or rose flowers in abundance from May to June.
A few of my favourites include ‘Freda’ (deep pink w/ bronze foliage), ‘Grandiflora’ (pure white), and ‘Fragrant Spring’ (scented pale pink). For later blooms you have the choice of the ‘orange peel’ clematis or C. tangutica ‘Golden Harvest’ (June-Sept) and the precocious Sweet Autumn Clematis (C. paniculata) which bears thousands of white hawthorn-scented flowers from late summer into the fall.
Cold-Hardy Clematis
Many of those who live in exposed sites, at higher elevations or have a cabin in the interior have accustomed themselves to plant failures over the years. But there are many clematis that tolerate climate zones as low as USDA zone 3 with snow cover and these include many ‘C’ pruning group types, as well as those in the Clematis viticella species, many of which were bred in Poland.
Some ‘C’ group choices include ‘Jackmanii’ (purple), ‘Margaret Hunt’ (dusky-pink) and ‘Rouge Cardinal’ (burgundy-crimson).
The viticellas are plentiful and quite varied in flower colour. Here you will find white with contrasting purple stamens (‘Alba Luxurians’), rosy-red (‘Kermesina’), pale blue (‘Blue Angel’), bicolour purple-white (‘Venosa Violacea’) and even wine-red (‘Madame Julia Correvon’).
Shade-Tolerant Clematis
We’ll begin by defining shade tolerant, which in the case of clematis does not mean deep dark shade with no signs of light. What some varieties will tolerate is open shade, or areas where some light is still able to penetrate such as beneath a tall tree canopy or a northern exposure that only gets a few hours of sun early or late in the day.
Here you want to focus on the nodding blooms of Clematis alpina or macropetala, with ‘Stolwijk Gold’, ‘Blue Bird’, and ‘Lagoon’ all being good choices, respectively. The good news is that even older large flowered hybrids can be selectively used, including ‘Dr. Ruppel’ (bicolour pink), ‘Countess of Lovelace’ (dbl. blush lilac), ‘Henryi’ (pure white), and ‘Veronica’s Choice’ (dbl. French grey and pink).
Clematis for Sheer Beauty
There are a lot of clematis that should be grown just for their sheer beauty and the best place to start is with Clematis florida. Whether you choose Evison’s ‘Cassis’ (dbl. plum-purple), ‘Taiga’ (lavender-purple) or the much older ‘Sieboldii’ (white with purple stamen boss) and ‘Alba Plena’ (semi-dbl. white with green highlights) you can expect stunning blooms for months on end.
Bicolour singles such as ‘Joan Picton’ (purple w/ white bar), ‘Kilian Donahue’ (fuchsia pink w/ ruby-red bar), and ‘Mrs. N Thompson’ (violet-purple w/ red bar) are all in a class by themselves.
Let’s not forget those doubles. These are true clematis royalty and include ‘Multi Blue’ (balled dbl. blooms), ‘Violet Elizabeth’ (thick mauve-pink blossoms), ‘Vyvyan Pennell’ (ruffled violet-blue), and the regal ‘Duchess of Edinburgh’ (creamy-white).
Clematis that Defy Classification
Last but not least are those varieties that seem to defy classification such as ‘Joe Zary’ (dbl. purple octopus form) and the eye-popping ‘Avant-Garde’ (deep magenta with pink stamen boss), a popular cultivar from Evison.
Needless to say, there is no shortage of clematis to meet both your aesthetic and microclimate needs, and by sheer coincidence, all of the varieties profiled in this article are available on our presale website, which is just a click away.
