Abigail McLellan: Scottish artist celebrated for her use of intense colour and pared-down images

In March this year Abigail McLellan came down to London from Glasgow for the Private View of her new exhibition of paintings at the Rebecca Hossack Gallery. She arrived in a wheelchair. The multiple sclerosis that had already robbed her of mobility was beginning to effect her speech. Yet she was readily able to communicate her excitement; while the pictures on the walls proclaimed not only a rare artistic vision but an indomitable creative energy.

Scotland has more than its fair share of grey days. And it is perhaps for this reason that Scottish painters have come to understand and to celebrate colour with such verve. Abigail McLellan certainly understood and celebrated colour in her paintings: pared-down, almost abstracted, images of single plants, flowers, and other distinct items, set against richly-worked backgrounds of saturated colour.

McLellan herself was also full of colour, with her red hair, her pink cheeks, and a sense of humour that brought light to so many situations. And it was with both humour and extraordinary fortitude that she faced the illness that remorselessly destroyed her body and led to her death at the age of 40.

Abigail McLellan was born in 1969 in Middlesbrough, where her father was working as an engineer for ICI. Having two older and scientifically inclined sisters, she developed an independent spirit and an enthusiasm for art. From an early age she marshalled her father's engineering expertise to help with her many ambitious primary-school art projects. These included an Easter Bonnet topped with a cardboard merry-go-round, and – in 1977 – a fancy-dress costume in the form of a giant Jubilee mug.

When McLellan was 12 the family moved to Dumfries, and it was in Scotland that she completed her education. In 1987 she went to Glasgow School of Art, joining an exceptionally talented and vital generation of young artists, including Chantal Joffe, Helen Flockhart, Peter Thompson and Alasdair Wallace. (Wallace became her life-long partner; they married earlier this year.)

It was a time of experiment and discovery. McLellan's student works included a Joseph Beuys-inspired jar lined with lard and bristling with tiny spikes, a deckchair adorned with images from Gray's Anatomy, and a series of bold, chunky portraits. Only towards the end of her time at GSA did she begin to develop her distinctive voice as a painter.

McLellan's vision, for all its individuality, drew strongly upon the traditions of Scottish – and, particularly, Glaswegian – art. Her striking simplifications of form and her bold sense of design owed much to the late 19th-century Japonisme of Charles Rennie MacKintosh, James MacNair and the Macdonald sisters, Frances and Margaret. A similar sense of compositional daring was also one of the traits that she admired in the work of Craigie Aitchison. She was touched, too, by Aitchison's sense of humour, his directness and – above all – by the range and richness of his colour-palette.

In her own quest to create a comparable intensity of colour she evolved a highly personal technique, building up layer upon layer of translucent, quick-drying acrylic paint in short, stippled strokes. The objects that she set on these luminous backgrounds – flowers, tree-branches, sea-fans - were often defined by their "negative space". She would, as she put it, paint "the in-between bits".

Her approach proved remarkably productive and flexible. She described the "Eureka moment" when she saw a friend at a nightclub, wearing a red dress and sitting at a little round table, and suddenly grasped how she might adapt the subtle stylisations of her still-life work to portraiture.

A succession of brilliantly successful portraits followed. From 1995 she exhibited regularly at the National Portrait Gallery in the annual BP portrait awards. She won the Morrison Portrait Award from the Royal Scottish Academy in 1997. Her layered and ordered technique was also well-suited to screen printing, and she made several successful prints with the Glasgow Print Studio. In recent years she even extended her method into sculpture, makings a series of bronze-cast coral "Sea-Fans".

Ten years ago, having just become an enthusiastic walker, she began to fall over. Multiple sclerosis was diagnosed. It was, as Wallace, remembers, "a cosmic kick in the teeth", but McLellan refused to be cowed. She continued to work – and to walk. Doggedly ignoring the lift, with her crutches in one hand and the banister in the other, she would climb four steep flights to her studio every day for as long as it was possible.

She was blessed with a strong streak of stubbornness. To every setback she would seek a solution. As her mobility declined, she embraced the internet – not only to feed her insatiable curiosity about the worlds of art and design but also to source gadgets and equipment that might make the practicalities of life easier. When the right equipment could not be found, she would devise it herself with elements bought from the local climbing shop.

Throughout a decade of worsening illness, McLellan continued not merely to practice but to develop as an artist. Her work lost nothing of its intensity and invention. She was, though, obliged to adapt to the cruel facts of her physical decline. Her painted forms became bolder and more abstracted. She began to experiment with stencils and to employ assistants to build up the carefully-layered backgrounds of her paintings. Her talent and creativity – together with the loving support of Alasdair Wallace - sustained her to the end. She was in the studio the day before she went into hospital for the final time. She expected to be back.

Matthew Sturgis

Abigail McLellan, artist: born Middlesbrough 11 July 1969; married 2009 Alasdair Wallace; died 11 October 2009.