I originally hoped to use digital images of actual vintage fabrics, but they were neither specific enough to the books nor consistent enough in color and contrast to serve my purposes well. Instead, I essentially crafted my own "fabrics" by finding digital patterns, recoloring them as necessary, and "tiling" them into single images large enough to create the background for each cover. With their stitch design, the labels and ribbons of each cover referred back to the idea of textiles, broke the strong patterning, and gave me space for necessary text. I added the first ribbons to cover a slightly awkward central join in one of the patterns, but came to like the vertical element it added.
Each background references the story of its book, whether directly (the horses of Airs Above the Ground, the tree of The Ivy Tree) or indirectly (the Greek key motif of My Brother Michael, the stained-glass-inflected pattern of Thunder on the Right, or the Provencal fabric design of Madam, Will You Talk?). I wasn't literal, however; the birds on Stormy Petrel are not petrels and the cougar, whose spots are the source of the motif on Touch Not the Cat, is neither technically a cat nor the tiger the book actually describes.
Readers could grouch at that—I've been one of those grouching readers myself looking at others' covers! But for me, the creative brief here was not to illustrate the novels in any literal way but to capture their spirit. To my own eye, at least, this series approach gives a playful and affectionate wink at the books' original era without mimicking vintage or retro design.