Her eyesight is failing and she can’t read much anymore, but that hasn’t dampened the Dowager Duchess of Devonshire’s passion for the written word — preferably handwritten.

“I can’t do e-mail. I’m too old and too stupid,” says the 89-year-old former chatelaine of Chatsworth, one of England’s grandest estates; widow of Andrew, the 11th Duke of Devonshire, and the youngest — and last surviving — of the six charismatic Mitford sisters. “I love getting letters. I like the stamp on the envelope and the excitement of the postman arriving. Don’t forget, I’m nearly a hundred years old.”

Deborah Devonshire — Debo to her family and friends — pens most of her correspondence from home, a cottage known as the Old Vicarage on the family’s 1,000-acre Derbyshire estate. (Her son Peregrine, the 12th duke, and his family now live in the grand house.) She is a faithful letter writer to friends such as Patrick Leigh Fermor, the British travel writer who famously walked the length of Europe in the Thirties. But recently the duchess has turned her focus to books. In 2001, she released “Counting My Chickens: And Other Home Thoughts,” followed by “Home to Roost and Other Peckings,” a collection of essays, diary entries, speeches and articles that was published in Britain last month. Now Devonshire is tackling her largest project to date: her memoirs.

“It’s all about my long, boring life,” says the woman who had tea with Adolf Hitler in his Munich apartment; befriended the Kennedy clan when they moved to England in 1938 (the late Kathleen Kennedy later became Debo’s sister-in-law), and whose family tree includes former prime ministers Winston Churchill and Harold Macmillan.

Nevertheless, she says, “It is funny what stands out in the memory — the pain I felt leaving our house in Oxfordshire when I was 15, because my father could no longer afford it. To me, it felt like an amputation, although my sisters couldn’t wait to leave. And the extraordinary experience of coming out,” she adds, referring to her society debut in 1938. “It was quite incredible!”

“Home to Roost” includes memories of John F. Kennedy’s inauguration and funeral, her musings about tiaras and old age and the perils of buying clothes when you can’t see the colors properly. There is an ode to her local post office, which recently shut, and recollections of fashion shoots at Chatsworth with Bruce Weber, Mario Testino and her granddaughter, Stella Tennant. “Bruce made me wear a red satin Balmain ball dress to feed my chickens,” she writes. (Those chickens earned their keep: Devonshire would sell their eggs in her farm shop in the village and she later opened a branch in London selling foodstuffs made on the estate.)

It’s unlikely that Devonshire’s latest life story will include much fanfare over clothing. She doesn’t shop much these days, and why would she when her closets are filled with Lanvin, Balmain, Dior and Oscar de la Renta, who, with his wife Annette, often visited Chatsworth. As she says, “My children and grandchildren say I must start an archive.”

When the duchess does decide to splash out, she heads to her nearest agricultural show. “I can find nice, thick clothes for Derbyshire winters,” she explains, although her outdoor pursuits have become limited to feeding her chickens and tending to her garden. “I’m too old for horses and too lazy for dogs,” she says.