Clematis (Clematis spp.)

They are delightful moderate to vigorous climbers with vibrant flowers in tones of pink, mauve, purple, red and white. Some species have yellow flowers. Plants flower from spring to summer, and many also continue to flower well into autumn. Most are deciduous climbers, but there are also some winter-flowering and evergreen species.

Some clematis species can climb more than 5m high, but others are smaller and well-suited to growing on tripods or trellises. Clematis plants do not thrive in containers for long periods. However, if a pot is the only option, choose a large ceramic pot to provide enough space for the roots to grow and to help keep them cool. Use a premium potting mix such as Seasol Advanced Potting Mix for healthy growth. Choose a small-growing variety and train it up a tripod or against a trellis.

Clematis grow best in cool climates with regular moisture and are very popular garden plants in areas where they thrive. Clematis plants are mainly native to China and Japan but have been widely hybridised and are grown throughout the world.

After the petals fall, the central boss persists, especially on the Clematis montana varieties, which develop fluffy silvery seed heads that look ornamental. The fluffy seeds give clematis the common name of old man’s beard and traveller’s joy.

There are thousands of named clematis varieties available. For a clematis to suit your location, check out your hardware or garden centre for great advice on a clematis to suit your space and climate.  Here are a few to look out for:

  • Clematis montana is one of the easiest to grow and quickest to flower if you are new to them. It is a vigorous, frost-hardy deciduous climber known for its beautiful spring flowers in shades of white, pink, or red and lush green foliage.
  • Clematis montana ‘Elizabeth’ is a beautiful, vigorous deciduous climber named after Queen Elizabeth II with fragrant pink spring flowers adorned with a satin sheen and pale yellow stamens. Flowering from late spring to early summer, it is distinguished by its mid-green foliage.
  • Clematis x Jackmanii Hybrid ‘Niobe’ has beautiful big blooms with red, ruby, velvet flowers with yellow anthers from spring to autumn. A small deciduous climber, it is ideal for small gardens or containers where it looks stunning combined with small to medium plants.
  • Clematis x Jackmanii Hybrid ‘Cotton Candy’ is a moderate, deciduous climber growing around 1.2 to 1.8 metres tall. It has stunning white flowers with mid-pink bars with yellow stamens from spring to autumn.
  • Clematis aristata also known as goat’s beard, is an Australian woody climber to around 15 metres tall. It has creamy white star-like flowers with yellow stamens from spring to autumn.

All clematis can be trained to grow against a wall, over an arch, across a pergola or along a fence. Clematis hybrids are often grown with blossom trees and allowed to climb into the trees. As they are light climbers and regularly pruned, they rarely damage trees.Growing conditions

Growing conditions

Aspect Clematis need a bright, warm, sunny location with cool soil to protect its roots.  A sheltered aspect with morning sun and some afternoon shade is beneficial, and protection from strong winds is important.

Soil These plants grow in a wide range of soils but do best in well-nourished, fertile soils with reliable moisture but good drainage. They do not like waterlogged soils. Before planting, add home-made compost and organic matter and/or Seasol Super Compost

Climate Clematis need a cool to mild climate, especially a cool summer. Hot summer conditions are not favourable for clematis.

How to grow and look after clematis for climbers with beautiful white, purple, red, or pink flowers including soil, planting, and feeding
How to grow and look after clematis for climbers with beautiful white, purple, red, or pink flowers including soil, planting, and feeding

General care

Watering Clematis need regular water through the warmer months of the year. Plants that dry out may die back or can die off completely.

Feeding and mulching These plants grow and flower better with added fertiliser. Feed throughout the seasons using a complete fertiliser for flowering plants such as Seasol plus Nutrients Roses & Flowers. Supplement feeding with a liquid fertiliser such as PowerFeed PRO SERIES for Roses & Flowers every 2 to 4 weeks. Plants in containers can be liquid fed every 2 to 4 weeks while they are growing and flowering. Apply PowerFeed PRO SERIES Roses & Flowers or PowerFeed All Purpose including Natives. Regular applications of Seasol also assist drought hardiness and disease resistance.

Keep the root area well mulched to keep the roots cool and moist. Some growers also keep the soil cool with flat rocks placed over the root area, but don’t block out moisture.

Pruning Pruning is done in autumn or winter according to the classification of the variety as Group 1, 2 or 3 (check the plant’s label for this information).

As a guide, most hybrid spring- and summer-flowering varieties are cut back hard in winter to encourage strong new growth. Clematis montana and native clematis only need to be pruned to control their growth and spread, so they are not cut back hard in winter.

Watch out Clematis are rarely attacked by pests or diseases, but may suddenly wilt and die due to root disease or adverse growing conditions. When this occurs, cut the clematis back and water and apply Seasol regularly. When new growth resumes, liquid feed with PowerFeed PRO SERIES for Roses & Flowers to encourage new growth.

Some varieties can suffer from powdery mildew, which can be controlled with a fungicide spray and by improving light levels and air circulation.