“Black” is usually shades of purple and green: (clockwise from top left) Cotinus coggygria ‘Velvet Cloak’, Cimicifuga simplex ‘Hillside Black Beauty’, annual millet Pennisetum glaucum ‘Purple Majesty’, Acer palmatum variety, Hibiscus x moscheutos ‘Kopper King’, Ligularia dentata ‘Britt-Marie Crawford’, Ipomoea batatas ‘Blackie’ next to heart-shaped Cercis canadensis ‘Forest Pansy’, Weigela florida ‘Fine Wine’ with Trillium fruit, daylily flower Hemerocallis ‘Jungle Beauty’, strappy black leaves and pale flowers of Ophiopogon planiscapus ‘Nigrescens’, Ajuga reptans ‘Catlin’s Giant’, maroon leaf of beet Beta vulgaris ‘Bull’s Blood’, Begonia ‘Black Fang’ to its right and Geranium maculatum ‘Espresso’ above it.

 

White and black are missing from the color wheel. Black is theoretically the absence of color—the absorption of all light. White appears when all colors are together, and all light is reflected at once. If you were to spin the color wheel at high speed, white would appear. White is often used as an accent in the garden, either with flowers or more permanent elements like a fence or latticework. Some gardens are made with only white flowers. It is not too hard to arrange when they are all white— from short to tall and relationships of texture and scale.

Whether a hue appears vivid or subdued depends on how saturated the color is. Color value is how light or dark the particular color appears. Maroon is darker in value and pink lighter than their parent hue: red. When mixing paint, adding white to a color pigment creates a tint or pastel. Pale flowers are lighter versions of hues, like ivory from yellow. Likewise, colors might appear as shades—darker versions of colors made when black is added to a hue. Tones are subdued by adding gray, brown, or a color’s complement (found directly across from it on the wheel) to the pure, vivid color: army green from green.

What we call black plants are usually ones that are just very dark hues. What appears black in the garden is what we see in contrasting shadows in bright sunlight. There’s not much one can do about the high contrast observed on a sunny day. I don’t like to photograph a garden in full sun, and frankly, I prefer not to even view one under such conditions. In the subdued light of an overcast day, plants look their best. Colors appear richer, and there is more visible variety. The eye can drift from the front of the planting to the back without being stopped by blinding, washed-out flowers with no apparent detail, or black holes made by shadows.

When mixing paint colors, adding white creates a pale tint; adding black creates a dark shade. White is represented here by tender, tuberous white dahlias, spidery annual Cleome ‘Helen Campbell’, and feathers of tender perennial Salvia farinacea ‘Victoria White’.

Pale-colored buxom peony blossoms contrast with the little light pink trumpet flowers from old-fashioned beauty bush, Kolkwitzia amabilis.