Trellis Tips

Trellis Tips – do your climbers look gorgeous?

or do they resemble a plate of spaghetti falling off the fence?

Trellis Tips for unravelling that spaghetti!

Trellis is a wonderful way to get plants up to our eyeline so we can enjoy and smell all those gorgeous flowers. Sadly though most of domestic garden trellis rarely look this good.

trellis tips

So, what went wrong?

There are three main problems that occur with trellis and climbing plants.

  • The wrong sort of trellis is used.
  • The wrong plant is growing on the trellis.
  • The planting and siting of the trellis is wrong.

Or it is a combination of all 3….in which case the best option is to start again entirely. But let’s deal with the main causes of problems.

What trellis to use?

There are two main types of climber most of us grow, ones that we plant in the spring, that flower in summer and then die – Annual climbers. Then there are the the everlasting climbers. These come in a few size categories, 6ft or less, large and heavy, really large and really heavy and finally ‘requires industrial strength fixings’ or a tree to support it! There is the start of a theme here.

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Annual Climbers:

Let’s deal with annual climbers, things like Sweet Peas, Nasturtiums, Black Eyed Susan etc. These are short lived, thin stemmed, lightweight and not very thuggish. So all the pretty wicker trellis, plastic trellis and small obelisks etc are perfectly strong enough to cope.

As the plant dies in the autumn, it shrivels and the stems are easy to remove without breaking the trellis.

Perennial Climbers:

Now the perennial climbers – Roses, Clematis, Honeysuckle, Wisteria, Jasmine and so on. Wicker or plastic trellis are simply not going to be able to cope with the weight or the vigour of these plants. You need to have really sturdy trellis supported on really sturdy fixings to cope.

Take this picture. The rose exerts a huge stress force on the trellis as it grows out toward the sunshine. Even this sturdy trellis can be broken by the growth of the stems. A couple of wall screws & rawlplugs are not going to last very long when you have the added elements of the extra weight when wet and wind rock to contend with.

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In conclusion, if you plant anything that will last more than a few months – you need to buy the strongest trellis you can. If the plant says it will grow to 10 feet tall in 5 years, then the trellis needs have at least 10 feet for the plant to grow along.

You can choose smaller trellis obviously, but then you will have to constantly reduce the size of the plant. And you need to be sure you have the time to devote to that ongoing battle.

Good Trellis – Wrong Plant

All plants on trellis need training to the desired shape or tying in – and this takes time. Some plants ‘tie’ themselves in and some plants can self cling, which sounds great until you need to untangle them.

If you intend to grow a plant up a trellis next to a fence or wall, then avoid these plants as they quickly resemble spaghetti!

Top trellis tips – Avoid the following:

  • Potato Vine or Solanum
  • Honeysuckle
  • Forthysia
  • Clematis Montana
  • Clematis Tangutica
  • Passion Flower
  • Polygonum or Mile a Minute (but you should never have this in a garden anyway!)
  • Chilean Trumpet Vine or Campsis- this is a triffid, a very pretty one but a total triffid!

All these plants are probably best displayed on a pergola rather than a flat fence.

Keep Well Trimmed:

There are some plants that do grow quickly, but you can easily cut them back to keep them in check.

  • Golden Hop – this will probably grow too fast for most fences but it does dies back.
  • Virginia Creeper
  • Jasmine
  • Ivy

The other plants such as Roses, Clematis, Wisteria all need proper pruning each year, but if done, these will all happily grow up the trellis.

Finally, Planting and Siting:

All plants needs three things to grow, food, water and light. The problem with trellis on walls is that usually once the trellis is on the fence or the wall the plant ends up missing out on at least one of the vital elements.

Here for example, although this is a self clinging plant, it has raced up the wall to try and reach the sunlight.

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As well as having nothing to grow on, this rose will never thrive. It is planted too close to the base of the wall thus starving it of nutrients and water.

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This last trellis is fixed flush to the wall, is under a deep roof eave and the roots will be in a rain shadow. So pretty tough growing conditions for anything to look good!

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Over time all plants will grow away from the fence. If however the trellis is fixed flush to the fence, the plant will grow unevenly it will suffer from leaf drop.

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When attaching a trellis to either a wall or a fence, the best way is to use a bracket. The trellis can be hung on the bracket, so if the fence needs a lick of paint, it is simply unhooked and laid flat.

Plant the base of the plant as far away from the base of the fence as possible also.

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Trellis Tips:

In conclusion, always buy a bigger and stronger trellis – it won’t disappoint, even though it cost a bit more. Think carefully the type of plant you are displaying. The trellis must be large enough for the plant to grow. Some plants look best on posts and pergolas, so think carefully whether it can be trained to grow well against a wall.

Think light, food and water before planting – make sure the plant can access all 3. If you don’t the plant will become very high maintenance!

Lastly, use a detachable fixing – it saves so much aggravation in the long term.