Relentless Gardener: Cultivating Clematis

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There are over 230 Clematis species, both woody and herbaceous types. Among the 230 species, there are climbing and non-climbing varieties. The non-climbing species are C. heraceifolia, C. integrifolia, and C. recta.

What are some of the most popular cultivars of Clematis? Clematis ‘Jackmanii’ is a late summer clematis with four petals with velvety dark purple fading to violet as they age. It was introduced back in 1862! Sweet Autumn Clematis, Clematis terniflora is great for growing on trellises because it can grow 15-30 feet in a season. Clematis ‘Nelly Moser’ grows better in cooler climates but still does well in the heat. With ‘Nelly Moser,’ this does not have to be pruned because it blooms on old canes. Clematis Josephine ™ needs some shade to prevent fading.

Fertilization of clematis is usually done in early spring before the vine forms flower buds. After that, it isn’t necessary. It is important to have the soil slightly acidic from 6.5 to 7.0, in well-drained soil. Their roots need to stay cool and their heads hot. Hence the expression “heads in the sun” and “feet in the shade”.

With pruning, there are three different groups:

• The first group is spring bloomers that bloom on old wood.
• The second group is repeat bloomers that bloom on old and new wood.
• The third group is summer or fall bloomers that bloom on new wood.

For those varieties that bloom on new wood, you prune in late fall and winter or very early in the spring before new growth. For varieties that bloom on old wood, prune after the clematis is done flowering. Regular pruning is necessary to promote flowering and ensure strong growth.

Clematis can tolerate wide exposures to the climate and various tolerances to heat and cold. They come in all shapes, sizes, and colors to suit any garden. If you do not have a clematis, give one a try.