Garden greenery – Illuminating the foliage on trees

We assume that light is able to enhance the strong points of a given space and (literally) put its weaker points in the shade. The first questions to ask are:

In a garden, as with architectural lighting, the light is subordinate to the architecture of the space to be enhanced.

The first point on our imaginary check list will therefore be to understand the setting’s morphology: where we can go full speed ahead and where we need to move more cautiously.

We can judge whether to concentrate the observer’s attention on specific subjects, such as a group of plants, a sculpture, the flowerbeds, a walkway, a fountain if there is one, or the foliage. This will help us to create a mental map of the areas on which to concentrate to avoid confusion and overlapping lighting effects.

Let’s assume that, in a garden, the most spectacular element to be highlighted is the crowns of the trees: we’ll start there.

We probably need to open a large parenthesis here: what kind of trees are we talking about? What kind of foliage? As you can probably imagine, every type behaves differently, so an assessment of where to position the lighting fixture needs to be carried out for each one:

below the foliage,
among the foliage,
at a distance from it.

To understand where to position the light, we need to first ask ourselves what lighting effect we want to achieve. Only after that should we ask ourselves where the lighting fixture needs to be to obtain that effect.

A dramatic effect, usually characterised by a lot of contrast between light and shadow, is associated with a desire to attribute solemnity and majesty to a subject.

This is particularly used on column-like foliage, such as that of cypresses, which have a compact shape with clean contours. The effect can be achieved with recessed luminaires or projectors with medium-narrow optics, between 10° and 40°, placed at the base of the trunk.

The bottom-up lighting elongates shapes to imposing effect.

You can add further drama to the scene by working with colours, especially if the light is a deep red :)

Here, instead, we can see the example of light applied from below to a dome-like canopy, like that of Japanese maples. The serrated outlines of this type of foliage soften the contrast between light and shade, but the overall structure remains clear.

If the plant’s shape hinders the passage of light coming from below it, the fixtures need to be set at a distance from the trunk, with an increased number of light points, and wider optics.

In the example on the left, the branching on the plant starts at the base of the trunk, and fixtures with equal intensity, positioned at different points, allow us to appreciate its spread. 
In the example on the right, on the other hand, it is the breadth of the foliage, the umbrella-shaped canopy, of the common hornbeam that is being highlighted.

Up to now, we have concentrated on the foliage’s outer shape, as if it were a closed shape. Let us suppose, instead, that a tree's beauty lies in its internal branching and that we are searching for a lighting effect that emphasises its inner part, if necessary leaving the leaves in silhouette (lighting the negative space).

In this case, we can “climb” our light inside the tree, by fixing compact projectors on the branches with fastener straps. These are bands of soft fibres that can be easily loosened or repositioned without affecting the bark in any way.

If we like the effect of highlighting the negative space, we need to evaluate whether the tree’s foliage is not too thick and therefore unsuited to housing projectors within it. In that case, we will have to rethink and consider positioning the fixtures below the tree.

During the day, the light filtering through the branches creates the impression of a succession of planes; in the dark, however, if we point a projector head-on to foliage, the surfaces will appear noticeably flattened.
We know that positioning is everything when it comes to enhancing the three-dimensional effect.

Sometimes, though, there may be little room for manoeuvre in terms of where the fixtures are installed, and the lighting may be the only variable available.

Does this mean we have to forego a lighting effect that covers the whole canopy?
Certainly not.

We are aided by an accessory that we added to our catalogue in 2017 on the recommendation of lighting designer Francesco Iannone: the shadow-effect filter.

Compare the images A and B below, where the bamboo is lit by a 55W projector  at a distance of 2.5 m

By definition, nature is in a state of becoming, and in a garden this brings with it the need to adapt the lighting fixtures.

To address this age-old question, we have three solutions to offer you:

A. Using projectors with a manual zoom lens: adjusting the body of the fixture as if it were a camera lens alters the width of the light beam (9–36°).

B. Fixing the projector to a small stake  that can then be replaced with a larger one as the tree grows: an additional function for the stake, beyond the more well-known one of raising the fixture above the barriers that obstruct the lighting.

We were inspired by the lighting design by Susanna Antico Lighting Design Studio for Cascina Ranverso: here, the accent lighting on the young trees that line the entrance way from the main gate required the provision of stakes of different lengths so that the light source can be raised as the foliage on the hornbeams grows.

💡 📞 💡
Would you like an adjustable stake? Or perhaps a telescopic one?
Ask us about it, even if you can't see what you want in the catalogue: we can fulfil this and other special requests :)  

C. Replacing the optics: if the fixture is one in which the optics can be changed – by replacing a narrow beam with a wider one, for example – this is precisely the type of situation where this functionality comes into its own.

So far, we’ve talked about the different types of foliage and the different ways of lighting them; in the next post, we’ll talk about lighting tree trunks, shrubs, smaller plants and flowerbeds.