Scientists have created the world’s first all-black petunia plant, called Black Velvet. But, despite all the hype, it’s not really black – as Science Correspondent Tom Clarke discovers.

Petunias crossing to the dark side. Horticulturists today announced they have created the world’s first black petunia and it goes on sale in the UK in the spring.

The flower took plant breeders in the US four years to create. Now, after a year of field trials in the UK to ensure it can tolerate our climate, its creators are launching it here.

Stuart Lowen, marketing manager with the Banbury horticulture firm which developed the flower, Ball Colegrave, said: “It’s really quite an achievement to create a black flower, but for the customer it’s the intrigue, it’s sexy, it’s something different.”

In nature, flowers come in pretty much any colour you like – as long as it’s not black. The pigments that flowers employ to colour their petals don’t produce black.

But as any fashionista will tell you, anything goes well with black – a fact not lost on nursery men. So in the constant pursuit of new and therefore saleable varieties, breeders have long strived to produce blackest-looking varieties of flowers.

One of the earliest developed was the black tulip. There are now varieties of black rose, viola and hyacinth. The creators of the new petunia – dubbed “Black Velvet” – claim theirs is the blackest bloom yet produced.

“Novelty is always sought after in horticulture. It’s what entices people to buy plants,” said Janet Cubey of the Royal Horticultural Society.

Dark arts

However, getting a flower to look black isn’t easy.

“It takes a lot of breeding and selection to increase the levels of anthocyanins in the plant’s foliage,” said Cubey.

That chemical is part of the plant world’s limited palate for making colours. Anthocyanins can produce red and blue. By selecting flowers with the highest levels of these pigments and breeding them together, it’s possible to create very dark purple petals and leaves.

For that reason, the new petunia is in fact, like all “black” flowers, a very dark purple. Ball Colegrave claim that because petunias have a velvety texture to their petal, the bloom appears blacker than most.

Mr Lowen added: “It’s completely unique. It’s the first black petunia anywhere in the world. It was created by experimenting with existing colours already on the market and breeding them using traditional methods…

“They say black goes with anything, and it really looks exceptionally striking in the garden – it goes very well with whites, yellows and pinks. It’s rare to get a flower as black as this – very seldom do you get anything this dark.