Tag Archives: clematis

Climbing and clambering clematis

A selection of clematis which are still flowering in the garden, including two of the decorative seed heads

A selection of clematis which are still flowering in the garden, including two of the decorative seed heads

Clematis. I have not written about clematis before. This is in part that there is clematis specialist living around the corner from us and my technical knowledge on the genus is so sparse that I am worried about betraying my ignorance. I am terrified he will come and set me right. But they are such a lovely addition to the summer garden.

When I looked up clematis, I didn’t feel quite so bad about my botanical ignorance. It is a huge family with hundreds of different species (somewhere between two and three hundred or even more). Add to that the thousands of different hybrids that have been named. While ignorance may not be bliss, it is at least understandable in the face of such complexity. At least I found out that they are buttercup relatives – members of the Ranunculaceae family.

There are clematis and there are clematis. Some are altogether too vigorous. Who can forget “old man’s beard must go” on the telly? Clematis vitalba is such a strong grower that it threatens our native forest and can kill established trees. It is one garden escape that cost this country dearly. C. vitalba is not alone in its strangling and invasive personal habits but one hopes that somebody will have made those decisions long before you look at a pretty plant in the garden centre.

Clematis are equally notorious for karking it when planted out. That magnificent specimen in a pot with a frame covered in flowers can disappear before your very eyes when transferred to the garden. The problem is usually “clematis wilt”, reportedly a fungal affliction. If you spot it, cut back to healthy leaves, or even to the base of the plant if the whole thing is affected. Remove the diseased sections, cross your fingers and wait. Often, the plant will shoot again but it can take a while and the clematis roots can survive a year or longer without shoots above ground.

These are the only plants I know where the advice is to plant deeper in the ground than in the pot – around 8cm deeper is good. This is largely protection against the dreaded wilt, as far as I can see, so follow the advice. Like most climbers, they prefer their roots in cool, humus rich soil with adequate moisture levels but their heads in the sun. This is not always that easy to find, especially as you have to combine it with something for them to climb up. Once away, they can get purchase and twine onto surfaces that are not smooth – their instinct is to reach for the sun so most will climb if possible.

What we have as the tried and true "Nellie Moser" although it may be a seedling rather than the real thing

What we have as the tried and true “Nellie Moser” although it may be a seedling rather than the real thing

As garden plants, I favour the hybrids and the viticella types. We have a fair number twining their way through shrubs in mixed borders and they never fail to delight when they flower. You need to make sure that you don’t have overly rampant varieties when they are expected to co-exist with other plants. I took out what I think were texensis types – given to me as ground cover but distinctly shy on flowering, bell-shaped which I was not so keen on, and given to choking habits. I did not think they justified their position but there may be better texensis varieties available.

We have several growing under cover. Everybody admires “Niobe” in bloom. She has large flowers in deep burgundy but she proved damn difficult in the garden and it has taken several attempts over a fair number of years before we had a plant performing well, scrambling through evergreen azaleas. Planted in the ground but under cover with just some rain run-off to keep the roots moist, she has been much more reliable.

At the opposite end of the scale, the lovely, late-flowering yellow C. tangutica threatened a takeover bid in the garden but when relocated to a trellis under cover, behaved perfectly in comparative isolation.

Two named varieties. I just don't have the names any more.

Two named varieties. I just don’t have the names any more.

Often they can be combined with other climbers to extend flowering interest. We have clematis planted successfully with wisteria, Trachelospermum jasminoides and schizophragma. The latter two plants, for those who struggle with plant names, are a garden-friendly jasmine-type plant and a variation on the climbing hydrangea.

If you cut back most of the hybrids to just above ground level after flowering, feed and water them, you can encourage a second coming about six weeks later. Now is the right time to try this if you have some that have, as we say, ‘passed over’. However, it won’t work with the early spring flowering Clematis montanas. We don’t have C. montana any longer (it is a bit rampant for the garden, being better at covering old water tanks or sheds. It is once flowering only and needs different pruning treatment, if any. Most of the others I cut back to maybe 30cm above ground in winter and they are fine. Once established, they are easy and reliable and bring delight in spring and summer.

We have some lovely native clematis in this country but they are a story in their own right for another time.

An unnamed blue seedling that has settled down happily in a mixed border

An unnamed blue seedling that has settled down happily in a mixed border

If you want to know more about different types of clematis or maybe even buy mail order, my neighbour is http://www.mrclematis.co.nz/ (email: yaku@xtra.co.nz). He produces a phenomenal range and has a passion and knowledge for the genus way beyond mine.

First published in the Waikato Times and reprinted here with their permission.

Tikorangi Notes: Friday 13 January, 2012

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1) It is difficult to do justice to the Cyanella capensis in a photograph, but it must be one of the longest lasting summer bulb. It just gently flowers on and on in an unassuming way. “It looks like a blue gypsophila,” was Mark’s comment.

2) The weird and wonderful world of show vegetables – a competitive social phenomenon in the UK which has pretty much bypassed the more pragmatic gardeners in this country.

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Tikorangi Notes: Friday 13 January, 2012
I guess the one consoling factor in the continued run of dreary weather is that it is not limited to the area where we live! A misery shared is a misery halved, in the weather stakes at least. Even the Australian daughters are complaining about Sydney and Canberra weather and certainly it does not appear to be any better anywhere in the North Island of New Zealand. The raspberries are rotting before they have sweetened. The roses are mush. Anything bravely standing up is beaten down by the intermittent but torrential rain. The swimming pool cover remains resolutely in place. I have not even thought of going for a dip in recent weeks. The only consolation is that we know fine weather will return – it is just a matter of whether it is sooner or later.

The clematis remain valiant stars in all this dreary weather. We have lost the names on all of them though, should we feel the need, we know how we can get them identified. We have dug out the ones that are too rampant and thuggish in their ways and I remain unconvinced at the idea of ground cover types (too strong and choking). But given something to climb up, we have a range which are quiet and undemanding performers. All I do is cut them down once or twice a year to near ground level. Beyond that, they just get the standard treatment of other plants in the borders (a mulch of compost). I was told by a clematis expert that most of the hybrids can be cut back very hard after flowering, fed, watered and they will return with a new flush of blooms in six weeks time. I haven’t timed it, but it did make me realise that many clematis are not shy and timid plants and can take fairly ruthless handling. Should you feel the need to make a bamboo obelisk (you can just catch a glimpse of one supporting the clematis in the photo below, we gave step by step instructions in an earlier Outdoor Classroom.

The Turk’s cap and trumpet lilies are in flower with the auratums in heavy bud. It is the auratums that are the stars of summer display so we are hoping for better weather in the next fortnight.

Clematis with Loropetalum China Pink
Clematis with Loropetalum China Pink