Pia has worked freelance for the garden since 2001, creating signage and merchandising, often using the garden’s library of rare books for sourcing image material. One day, among rows of old herbals and engraved botanical works, she spied a hefty tome entitled The Ferns of Great Britain and Ireland by Thomas Moore (curator at the garden from 1848 to 1887), with pages displaying life-like and life-size images of ferns in colour. “They were too detailed to be drawn by hand but they certainly weren’t photographs,” says Pia. “I could feel the raised texture of the plants but the colour was too intense to be an actual pressed and dried specimen.” Puzzled, Pia noticed two words in the left-hand corner of the page: ‘nature printing’. Having moved from Sweden to London to study graphic design at Central St Martins, Pia was familiar with printing techniques but she still couldn’t see how these had been executed.

With her curiosity piqued, she started researching. “I first thought I could Google ‘nature printing’ but there was nothing out there,” says Pia. She eventually discovered that, while nature printing began simply as a method of inking up a leaf and taking an impression on paper (widely used by physicians to make plant records in the 15th century), during the 19th century a new form of nature printing was developed as new technologies enabled the production of printing plates.

Through endless enquiries and searches, Pia finally found all the pieces to the puzzle. A dried plant specimen was pressed into a sheet of lead and this impression was then copied using electroforming (suspending the piece of lead in an acid bath and, using an electric current, growing a layer of copper on it) to produce a copper printing plate. Numerous prints of the plant could be made. But the craft died out by 1900 – it was too costly and lithography took its place.

Pia has since taught herself the process of making the plates and has recently produced her own in her Hackney studio, which means she can now print as many giant oak leaves as she wishes and put together editions. She has also gone to great lengths to perfect her technique; working out the correct paper and inks, the extent to which she applies and wipes off the inking on the plate – even the number of blankets on the press. “I can see that the prints I’m making have the same quality as they had then,” says Pia. “I love how the physicality of the plant is transferred into the plate and the print is more like an X-ray. I also love that you can send a plate through the press and find this curious image at the other end.”

You can find out more about Pia’s work and what she is doing now on her Instagram page.