There's something odd and fascinating about coming across a flower that appears to be an endless hue of black. In truth, no flowers in nature can be completely black – most are deep purples.

Like the color blue, black simply doesn't occur frequently in natural foliage. Both colors rely on a chemical called anthocyanin, according to Janet Cubey of the Royal Horticultural Society. Careful selective breeding of flowers with high levels of these pigments can create a hue that's a dead-ringer for black.

Whether or not they're truly black, these darkly colored blooms add intrigue to any arrangement or garden. Symbols of elegance, power and mystery, black flowers are most often used for a dramatic farewell, according to a blog on Interflora. "A pure black flower is the Holy Grail to all flower breeders," Stefania del Zotto writes.

Take a look at some of the most stunning "black" blossoms.

'Queen of the Night' tulip

Queen of the Night tulips
'Queen of the Night' tulips are among the most beautiful nearly-black flowers. (Photo: Henry Hemming /Flickr)

Black tulips are a unique variety, quite unlike anything in a typical Easter bouquet. There was even a book of the same name written by Alexandre Dumas, with one of the plot lines being a competition to create a real black tulip.

Black dahlia

Black dahlia bud
The black dahlia is actually a very dark red. This dahlia bud is almost ready to bloom! (Photo: Steve Newcomb/Flickr)

Embodying the essence of mystery, this flower also made its way into the public consciousness. In fact, you may be more familiar with the 2006 film about the famously named murder victim from the 1940s than you are with the flower itself.

Hellebore

Black hellebore
This hellebore boasts a dark purple flower. When the shadows hit it just right, it looks black. (Photo: hailstone/Flickr)

Hellebore usually is white or pink, but the deep purple variety can appear black. Black hellebore is a poisonous plant and can even be deadly, adding to the intrigue of this peculiar plant.

Purple calla lily

Bride holds bouquet of purple callas
Purple calla lilies are a favorite for Gothic-style weddings. (Photo: marionhassold/Shutterstock)

Popular flowers for bouquets, purple calla lilies make a dramatic statement.

Bat orchid

Dark orchid flower petals resemble a bat
It's easy to see how the bat orchid got its name. (Photo: walterpro/Flickr)

Orchid breeders are hard at work attempting to create hybrids that are truly black, but this brownish bloom occurs naturally in nature. It's fitting that this fascinating flower, called a bat orchid, wears a dark shade.

Black pansy

Black pansy
Every now and then, a rare black pansy pops up in the garden. (Photo: Anna Bogush/Shutterstock)

Your regular, garden-variety pansy also comes in a deep purple variety that appears black, though it's rare. Keep an eye out next time you see a bed of flowers!

Purple petunia

Dark purple petunia
Some varieties of purple petunias are so dark they appear to be black. (Photo: GeNik/Shutterstock)

Petunias come in surprisingly dark hues. In 2010, horticulturists perfected a formula for a natural flower that is as close as possible to black, naming it the "Black Velvet" petunia.

'Black widow' cranesbill geranium

Black Widow geraniums
The 'Black Widow' variety of cranesbill geraniums are also known as dusky cranesbill and mourning widow because of their rich, dark hue. (Photo: free photos/Flickr)

A strange little bloom, Geranium phaeum goes by a few different names: dusky cranesbill, mourning widow and black widow. So it makes sense that this flower grows well in damp, shady areas.

Chocolate cosmos

Chocolate cosmo flower
Chocolate cosmos are a favorite 'black' flower all around the United States. (Photo: flowermedia/Shutterstock)

A plant native to Mexico, chocolate cosmos is a gorgeous maroon bloom. Not only does this bloom share a hue with chocolate, but it smells delicious too!

Black hollyhock

Black hollyhock flower macro
'Black Magic' hollyhock has us fooled! Its deep purple petals are very nearly black. (Photo: Aaron Carlson/Flickr)

Sporting the impressive name of "Black Magic" hollyhock, this variety of plants is a velvety bluish-purple, making for a unique deep hue.

Chocolate lily

Chocolate lilies
Chocolate lilies sport purplish-brown petals. (Photo: C. Rene Ammundsen/Shutterstock)

Unlike chocolate cosmos, chocolate lilies emit a rather nasty smell. Indeed, these gloomy blooms are pollinated by the most hated of insects: flies.

Anna Norris is an associate editor at Mother Nature Network. Follow her on Twitter and Google+.

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