The Upper Colquhoun Street mansion boasts a timeless blend of Mackintosh architecture and Art Nouveau features inspired by nature, 19th century literature, and fairytales.

Mackintosh was commissioned by the book publisher Walter Blackie to create the house and garden, as well as the interior fixtures and furniture, whilst Mackintosh’s wife, Margaret Macdonald, contributed many of the textile designs and a ‘unique’ gesso overmantel.

During this month’s Creative Mackintosh Festival, the Hill House will pay homage to the work of his wife and her legacy with the exhibition After Margaret.

Last Friday, the Advertiser was treated to a private tour of the property and visiting exhibition by Lorna Hepburn, National Trust Scotland property manager of the Hill House.

“We are very privileged to have this exhibition,” Ms Hepburn said. “People travel from across the world to visit the Hill House and this exhibition adds value to the visitor experience by providing a rare glimpse into Margaret’s gesso techniques, and allows visitors to see that there are people still working in gesso.” The exhibition depicts the various stages of making gesso, culminating in artists Dai and Jenny Vaughan’s homage to The White Rose and the Red Rose gesso panel by Margaret Macdonald Mackintosh.

Although Margaret was secretive about her gesso technique, Dai and Jenny inform visitors of their process with a step-by-step video.

Ms Hepburn added: “People are able to see how it was made, and they will be able to appreciate that is was a slow laborious process, which is not apparent when you view the work on the wall.

“Such care is taken by Dai and Jenny to get the reproduction just right – it’s not slap dash, it really is painstaking work.” Gesso is created using plaster of Paris, whiting, and rabbit skin glue and can take about a month to get the base formula ready for use. Layers of paint are applied before a tracing or drawing is made, and stones are cut to size to form the finished reproduction.

Jenny has also expanded on these techniques in other ways to create works including Tibetan Buddhist Tanka paintings.

As well as appreciating the skills of the two Vaughan artists, seeing the various stages of their work enables viewers to gain a further insight into the works of Margaret.

One of her most well-known gesso paintings, Sleeping Princess, sits above the fireplace in the property’s famous drawing room, designed by Mackintosh.

Ms Hepburn said it is unknown how closely Charles and Margaret worked together, however their creations sit in harmony throughout the house whilst threading together requirements of the Blackie commission, with five children in mind. She added: “You can get the impression Margaret and Charles worked together closely or collaborated.” Margaret was studying at the Glasgow School of Art with her sister Frances when she met Charles – an evening student – whose friend and fellow architect Herbert MacNair later married Frances.

After the group were introduced they became known as The Four, and their design work was a prominent feature of the Glasgow Style.

The Glasgow School of Art building is still considered one of Mackintosh’s masterpieces, however a ‘devastating’ fire at the design school in May acted as a reminder of the fragility of the Mackintosh legacy.

Ms Hepburn said: “The firefighters did a great job saving a lot from the fire and thankfully everyone got out safely but it really was devastating news.

“The library will never be the same again and now people who never visited have lost out.” After thrusting Glasgow on to the stage of the Art Nouveau movement, the international reputation of Charles Rennie Mackintosh and Margaret Macdonald continues to enshrine Helensburgh’s Hill House as a mecca for art lovers.

The After Margaret exhibition reflects their far-reaching legacy, which continues to thrive so long as the National Trust Scotland staff preserve the property to ensure the iconic geometric forms of the Mackintosh rose will forever be in bloom in Helensburgh.