ONE DAY at the dinner table, when Louise Bourgeois was a child, she kneaded her bread into a model of her father and ate it limb by limb. Even now at 96 years old, she is channelling her childhood pain into new sculptures, drawings, prints and paintings.

In those early days no-one was watching - but now Bourgeois is internationally renowned.

The artist grew up in 20th-century France at a time when the Surrealists were making their first forays into the unconscious mind. Associated with many artistic movements but pinned down to none, Bourgeois has spent a lifetime channelling her own stream of consciousness into latex, marble, paper, fabric and more.

Bourgeois was in her 60s by the time she gained substantial recognition as an artist, and she was past 70 when New York's Museum of Modern Art retrospective finally shot her to stardom.

In Britain, her massive spider (a tribute to her mother) for the brand new Tate Modern Turbine Hall made her a household name at the age of 88.

Edinburgh's Inverleith House is no stranger to artistic coups, and the gallery's upcoming show, Nature Study, presents an exclusive opportunity to see Bourgeois's latest outpourings. Twenty-five gouache drawings go on show for the first time, paired with 30 large-scale botanical teaching diagrams collected by Victorian botanist John Hutton-Balfour.

The pairing, inspired by a casual conversation between Edinburgh's Paul Nesbitt and New York-based curator Philip Larratt-Smith, is not an obvious one. Bourgeois's powerful visions of childbirth and breastfeeding are to be coaxed into conversation with Hutton-Balfour's big, brash close-ups of flowers, leaves, and botanical reproduction.

"Louise likes the idea," explains Larratt-Smith. "She doesn't have a scientific background, but she appreciates it. She sees the connections between the two." Bourgeois began making these drawings late last summer; starting off clean and precise, the red gouaches became increasingly wet, free and wild. The earlier childbirth images bear some resemblance to flowers, but not so the later works, which are soaked and streaming with raw emotion.

"My work is a series of exorcisms," Bourgeois has said in the past, and this is particularly true of her drawings. "When I draw, it means that something bothers me, but I don't know what it is." Freudian symbolism plays a major part - "tits and cocks" was all one bemused collector had to say after a visit to the artist's studio in the 1990s. Bourgeois's new work is no exception, breasts playing the largest role by far.

"The mother is represented by a part," explains Larratt-Smith. "A child needs to be connected to the breast and that's the only thing - it blots everything out in the same way that the red wash soaks everything else out of the watercolour."

The new gouaches are painful, furious, even aggressive. Pooling red paint, stabbed onto the paper, makes breastfeeding look like murder; sometimes the gaping-mouthed child is guilty, and sometimes it's the looming, prodding breasts. While Bourgeois herself is a mother of three, and at one stage she cared for her own sick mother, she is just as likely to see herself as the child.

"Louise has been getting down to essentials in her most recent work," says Larratt-Smith. "For a long time, her relationship to her father, and her fixation on her father and what he did to the family through his extramarital affairs, prevented her from being able to identify with her mother in the way she wanted."

Bourgeois's father famously had an affair with her governess while her stoic mother turned a blind eye. In Larratt-Smith's view, this childhood betrayal has been "overused by critics and art historians to explain a lot of her work".

"From the early 1990s onwards," he continues, "Louise has been turning more towards her mother. And part of that, I think, is simply because Louise, as she's been getting older and more frail, has become dependent on others and so finds herself in the position almost of a child."

The artist has argued that, like French wine, she gets better with age. Bourgeois still holds her famous Sunday salons in New York, inviting younger artists into her home to show her their work, but hasn't left her house in 12 years. "It's not because she's not able to," says Larratt-Smith, "she's just not interested any more."

For such a frail old lady, the intensity of the new gouaches is astonishing, and I ask the curator whether Bourgeois has a personality to match. "She's a pretty intense type of person," he confirms. "She's now mellowed, a little bit, finally! She's a survivor. Louise is not interested in fancy theories. She's interested in how to get through the day. In a lot of ways, these are really about survival and the possibility of her remaining connected to the things that matter."