Choosing the best large-flowered clematis for your garden

Boasting some of the most beautiful flowers of any vine, clematis produces abundant blossoms in a range of colours that include blue, purple, red, pink, yellow and white. Having trouble deciding which type to plant? Here's some help so that you can customize your garden perfectly.

[Image credit: iStock.com/prill]

The most commonly grown types are large-flowered clematis, which have showy star-shaped flowers up to 20 centimetres (8 inches) in diameter.

• Clematis vines typically climb by looping little leaf stalks (or coiled tendrils) around a neighbouring branch, wire, stake, trellis or other thin support. The plants can also be trained to drape over a fence, porch railing or lamp post to provide an eye-catching, colourful display.

If you'd prefer to grow clematis in a large container instead of having it crawl over a wall or support, you can outfit the container with a willow-pole teepee structure.

• Although the clematis won't grow as expansively, it makes moving the plant around more manageable since it's not rooted in the soil.

When the plant is not in flower, the leaves make a lovely screen – another reason why you may want to plant your clematis in a pot vs. having it grow vine-like and more "wild."

Either way, your clematis is sure to offer up a stunning floral display when in full bloom.

There are many varieties of large-flowered clematis, but most have showy flowers 15 to 20 centimetres (6 to 8 inches) across that are gorgeous and eye-catching. Most varieties will grow to about four metres (13 feet) in height, if you allow them.

Some varieties to consider include:

• Clemati × jackmani (Zone 2) which has abundant purple flowers for much of the summer, while 'Henryi' (Zone 4) lights up the garden with snow-white flowers ribbed in cream. These should both be pruned almost to the ground in spring.
• 'Nelly Moser' (Zone 3) is an older variety with pale pink blooms striped down the centre with a rose-pink band. This variety doesn't need to be cut back hard: just remove any old wood that doesn't show signs of growth in spring.
• 'Ville de Lyon' (Zone 3) has bright carmine flowers, and will reward you with two flushes of flowers if not pruned too hard in the spring. The first will be about 15 centimetres (6 inches) across and the second around 10 centimetres (4 inches).
• Another interesting large-flowered variety that flowers twice is 'Proteus' (Zone 4). Here, the flowers are double or semi-double in the first flush of blooms, and single in the second, but are full-sized each time. This variety doesn't need any pruning.
• 'Ernest Markham' has petunia-red petals that are rounded (rather than pointed) at the tip, with yellow stamens in the centre. 'Hagley Hybrid' is also sold as 'Pink Chiffon' and has shell-pink, cup-shaped flowers with brown stamens, while 'Gipsy Queen' is violet-purple with a velvety sheen and purple stamens. All of these are hardy to Zone 3 and need to be cut back hard in the spring.
• In Zone 4, you can also try the Canadian introduction 'Blue Ravine' with large blue flowers from early summer onwards. This variety thrives in the heat and should be planted in full sun.
• 'Rouge Cardinal' is a relatively new introduction from France and features crimson petals and buff-coloured stamens.
• 'Marie Boisellot' (also called 'Madame le Coultre') is a stunning sight. The flowers first open as a very pale pink then fade to white with age. It has exceptionally abundant, long-lasting blooms.

Because of their staggering beauty and unique look, it's easy to decide that you want to grow large-flowered clematis. The tough part? Choosing from the huge variety of types and species available. Your local garden centre experts can give you further advice to help you find the right type of clematis to enhance your home and garden.