Solar Spotlights: How to Uplight Trees, Planting and Sandstone Walls
Uplighting, grazing and washing techniques for solar spotlights, with advice on panel placement, glare and how many you actually need.
Solar Spotlights: How to Uplight Trees, Planting and Sandstone Walls
A spotlight is the most dramatic light in a garden, and the easiest to get wrong. Used well, one spotlight turns a tree into a sculpture and a rock-faced wall into a relief. Used badly it makes a harsh white blob on a flat surface and shines straight into the neighbour's bedroom. This guide covers how to aim, where to place and how many to use, with a focus on solar spotlights, which are the easiest to install and have the most trouble with placement.
What a spotlight is for
A path light marks the way; a wall light defines an edge; a spotlight picks out one thing. The aim is contrast. You want one or two bright spots against a darker background, because that is what makes a garden look deep at night. Lighting everything equally flattens it.
So begin by choosing the feature. Good candidates are a tree with a good trunk or canopy, a clump of grasses, a sculptural plant, a statue, a textured wall or a stone feature. If you cannot say what the light is for, you probably do not need it.
Three techniques
Uplighting: the light at the base, shining up
The classic method for trees and tall plants. Place the light on the ground a metre or so from the trunk and aim it up into the canopy or along the trunk. The effect is a glow that rises through the branches. Make sure the light cannot be seen from the main viewing position, for example by tucking it behind a shrub or a rock, because a bare bright source is glare.
Grazing: the light close to a textured surface
For a wall or a rock face, place the light low and close, a few hundred millimetres out, and aim it along the surface rather than at it. The ridges throw shadows and the stone looks three-dimensional. It works best on rock-faced and split-face finishes. See rock-faced sandstone blocks and sandstone boulders, and our finishes guide for how the surface changes with light.
Washing: the light further back, covering a wider area
For a smooth wall or a hedge, place the light two or three metres back and aim it so the beam covers the surface evenly. This gives a soft, even backdrop. It needs a wider beam and more output than a solar spotlight usually provides, so it works best on small surfaces.
The solar-specific problem: where does the panel go?
A solar spotlight needs two things that conflict. The light should be in the shade or beside a feature, hidden and aimed. The panel should be in the sun. If the panel is built into the light, you have to compromise. If it is on a lead, you can mount the light in the garden bed and the panel on a post in the sun.
Always check the position at midday. A beautiful uplight under a tree canopy will be dark by 9 pm because the panel never charged. Where the position is shaded, move the light, use a different feature, or choose a mains or 12V fitting. Our warm white solar spotlights are best placed where the solar panel can see the sky.
How bright is a solar spotlight?
Honestly, modest compared with a mains one. You will see solar spotlight listings that quote enormous lumen figures, and you should ignore them: a small panel and a small battery cannot deliver that. For ours, the supplier lists 52 warm-white LEDs and three lighting modes but does not publish a lumen figure, so we do not quote one. Think of them as accent lights for a small to medium tree, a shrub bed or a short stretch of wall, and use more than one if you need a stronger effect.
How many spotlights do you need?
Fewer than you think. One or two per feature is usually enough, and four to six accents across a whole garden, alongside the wall and path lights that give the general glow. That is why our spotlights come in a 2-pack and why they appear in our Sandstone Wall Lighting Kit and Entry & Garden Lighting Kit alongside other lights.
Colour temperature
Use warm white. Cool white looks clinical on foliage and can make green leaves look grey. Warm white keeps the colour of stone, bark and planting natural. Keep the same colour temperature across the whole garden.
Avoiding glare and light spill
- Hide the source. Position lights behind plants, rocks or garden edging so you see the effect and not the lamp.
- Aim away from the house and the neighbours. A light that shines into a window is a nuisance, and it is not good manners.
- Keep beams off the horizon. Aim up into a tree rather than out across the garden, so the light is not in anyone's eyes.
- Avoid pointing at glossy surfaces. A spotlight on a glass door or a pool surface creates a hot reflection.
Spotlighting a sandstone garden
Sandstone suits spotlighting because the warm tones of the stone respond well to warm light. A single low spotlight on a rock-faced wall, a pair on a pair of gate pillars, or one on a feature boulder can look better than a dozen general lights. If you are planning the lighting alongside the stone, see how to light a sandstone garden and retaining wall lighting ideas.
Setting up a solar spotlight step by step
- Choose the feature and the viewing position (where you will look from).
- Place the light so it cannot be seen from the viewing position, and aim it at the feature.
- Check that the panel gets several hours of direct sun; move the panel or the light if it does not.
- Switch on and leave to charge for a full day before judging.
- Check at dusk from the viewing position and adjust the aim a few degrees at a time.
- Revisit after a week and again in winter, when the sun is lower.
Common mistakes
- Aiming straight at a flat wall from a distance.
- Using too many spotlights and losing the contrast.
- Putting the panel in shade.
- Choosing a cool-white light for planting.
- Expecting floodlight performance.
Frequently asked questions
Can a solar spotlight light a tall tree?
A small solar spotlight gives a useful accent glow on a small to medium tree. For a very tall tree, a mains or 12V fitting will do a better job, or use several solar lights at different angles.
Why does my spotlight look harsh?
Usually because it is aimed straight at a flat surface from a distance, or the light source is visible from where you are standing. Move it lower and closer and aim along the surface, or hide the source behind a plant.
How far from a wall should a grazing light be?
A few hundred millimetres out from the wall is a good starting point, aimed along the face. Move it in or out a little at a time until the texture looks right at dusk.
Do solar spotlights work with motion sensors?
Some do and some do not. The three modes listed for our spotlights are not described in detail by the supplier, so we do not make claims about motion sensing for this model.
Bottom line
Pick a feature, hide the light, aim along or up rather than straight on, use warm white, keep the panel in the sun, and use fewer spotlights than you think. See the solar spotlights page for the range and kits.