High above Angie Lewin's studio in a verdant corner of Edinburgh, a buzzard circles lazily, as if truanting from a more rural world.

It's an apt backdrop to the packed windowsills of Lewin's city working place, her gleanings from the natural world stuffed into pots and scattered on trays amongst the printing presses and books. Here are brittle seedheads, twisted wrack from the shore, a striped feather; here are the long-held subjects of the artist's prints, familiar to many from greetings cards to book illustrations.

But it is Lewin's watercolours which are the focus of a new solo exhibition at the Scottish Gallery this month, her first to be made up entirely of paintings. Lewin has been making paintings alongside her prints ever since she graduated from Fine Art Printmaking at London's Central St Martin's in 1986. But if her prints are bold and busy, with a reduced colour palette, her watercolours are delicate and layered, using a wider range of colour. Pattern dominates, from plant structure to the images on the jugs which she uses in her assemblages. There is something rather joyous in the detail. "But I'm not after botanical accuracy," says Lewin, who tells me she exaggerates certain facets and plays with scale.

Born in Cheshire, Lewin lived in London and north Norfolk where she set up St Jude's, the printmaking studio, with her husband Simon Lewin, before moving fully to Scotland, splitting her time between Edinburgh and their cottage in Speyside.

It is out in the natural landscapes of Scotland and Norfolk that Lewin finds her inspiration, although Edward Bawden and Eric Ravillious are her artistic influences. "I do produce a lot of work," she says, as we flick through beautiful, detailed sketchbooks, the watercolour sketches ranging from the highly worked and coloured (produced in sunny Spain) to quick annotated pencil outlines (produced in a howling gale on Speyside). Once, on the west coast, she was so absorbed in her sketching that she did not notice a sea otter watching her intently, a couple of metres away.

She has been down on the ground, sitting amongst the plants, since she was a child. "Maybe it all relates back," she smiles. Then, too, came a post-college tilt at Garden Design, for which she completed an RHS certificate in Horticulture. "We had to make plant identification sketch books. Every week they would put ten different plants in jam jars. An allium was a stick with a circle on it. We'd think about design, about contrasting them with feathery grasses and umbels. We'd write about the plant's growth habit and where to grow it. And I think that's what awakened my interest. It's probably influenced the way that I draw plants as well."

Of the 18 Scottish Gallery watercolours, there is little sign in her bright studio beyond a stained palette. The paintings have already been delivered to the gallery. The bare bones are still there, though, in a pair of yellow pots of assorted gatherings from walks and sketching trips on top of a large plan chest. Miscanthus grass "possibly from Norfolk" sits fluffily next to the oddly animate seedpods of a "Mediterranean-looking" plant that Lewin found growing "not very happily" in her Edinburgh garden. "That is the arrangement for Spey Still Life With Yellow Book," says Lewin. "In a way the still lifes almost happen naturally because of the way I store things in pots."

Lewin surveys her collection of holey pebbles gathered in East Lothian, of giant mussel shells, of miscellaneous seedheads. "I like the way I work," she says. "I like the variety, of finding out if something is going towards a linocut or a woodcut, a watercolour or a fabric design. I like looking and seeing."

She smiles as she points out the "more real, more natural" outline of a broken poppy seedhead, jack-knifed rather forlornly in a pot. "I love that. I've got an endless source of inspiration here."

Angie Lewin: A Natural Selection, The Scottish Gallery, 16 Dundas Street, Edinburgh (0131 558 1200, www.scottish-gallery.co.uk), May 1- 30, Mon-Fri, 10am-6pm, Sat 10am-4pm