Lovell is a hearty, galumphing Briton of good pedigree and even better connections who once worked in corporate finance in New York. But on a whim, 15 years ago, she chucked that career to start the Rare Tea Company in London and has since devoted her life to advancing the cause of leaf tea (and to denouncing that epitome of foulness known as the tea bag). More important, she busies herself promoting those farmers around the world who grow tea and tend to it with the care and compassion that so ancient and elemental a beverage deserves and rightly demands. Her visits over a decade and a half to these faraway rural geniuses are what “Infused: Adventures in Tea” is about.

I had initially thought the book might be little more than an extended advertisement for Lovell’s business. But then I found myself quite caught up in her infectious enthusiasm as she ventured — twice defeating her own cancer, which tried in vain to slow her down — out into the world in search of the green tea hills in China, Japan and India, of course, but also in Malawi, Nepal and South Africa. On occasion, her style can be a little exhausting, with her bursts of Pete Wells-ian polychrome, but one can excuse her. This is a love letter, after all.