Why White Flowers Glow at Twilight
One of my favourite times to wander around the garden is after the heat of the day has passed and twilight starts to settle in. Everything feels a little slower. The colours shift, the shadows deepen, and the whole place starts to feel like a different world. Less about colour, more about shape and silhouette as things begin to blur into shadow.
It turns out there’s a name for at least part of what’s going on: the "Purkinje effect".
As daylight fades, our eyes become more sensitive to blue light, and the balance of colour we see starts to shift. Reds and pinks lose their punch, bright greens become more subdued, and the darkest foliage slips into shadow. Suddenly, you’re noticing the outline of a leaf or the shape of a plant rather than all the colours you could see an hour earlier. It’s almost as if the garden has decided to simplify its colour palette for the evening.
I notice it most with flowers. A red or pink bloom that was shouting for attention in the sunshine can become surprisingly dark as the light fades, while white flowers seem to get their moment. They catch the cool evening light and suddenly stand out against the darkening foliage, looking almost luminous. Of course, they’re not actually glowing. It’s our eyes, the fading light and that lovely contrast between pale petals and dark leaves doing the trick.
I love how quickly it can happen. One minute the garden is full of colour and the next it’s all deep greens, blue shadows and little flashes of white. The colours quieten, the shapes come forward, and those white flowers suddenly seem to hold onto the last of the light. For a moment, they become the brightest thing in the garden.
