Although Martha knows antique linens, the purpose of the buttonholes along the edge of one of her favorite antique linen sheets remained a mystery until she came across a picture illustrating the sheet’s use. After Martha discovered what it was meant to be—a decorative, detachable sheet that lines the duvet’s underside—she came up with some unusual duvet-cover-and-sheet combinations, all of which can also be used without the duvet insert in the summer.
To attach the linen sheet to a beautiful deep-green damask-covered duvet, Martha affixes mother-of-pearl buttons along three edges of the cover’s underside and several inches from its topmost edge, aligning the buttons to the sheet’s buttonholes. The sheet’s end flap folds over the top of the duvet cover so that its beautiful lace cutwork is visible, while the color of the buttons contrasts slightly with the sheet’s.
For the first of her two variations, Martha uses grommet eyelets and grosgrain-ribbon ties to secure a flannel sheet to the underside of a brown-ticking duvet cover. Then, for a Cobblefield-tartan duvet cover, she develops a technique that allows her to show off a pristine nineteenth-century American homespun sheet: She sews 1-inch grosgrain ribbon loops onto the sheet and attaches corresponding buttons to the duvet cover; the buttons and ribbon loops will be concealed, but to show a little more of the unusual sheet, which is made of flax, Martha allows its excess width to extend beyond the edges of the duvet.
When customizing your duvet, use as long a sheet as possible to ensure a generous flap. Keep in mind that manufacturers’ lengths vary, even within one brand. For twin- and full-size duvets, use a sheet one size larger than the duvet; since queen- and king-size sheets are the same length, use a queen-size sheet and a king-size sheet for queen- and king-size duvets, respectively. You can also use any homespun, flannel, or antique sheet or linen you may have at home.
Except in the case of the third example (Martha’s Cobblefield-tartan duvet cover), the width of the sheet should equal the width of the duvet, plus 1 inch for a seam allowance. You need only cut one side of the sheet, then hem it: Turn under the raw edge 1/2 inch, and press; repeat this process, creating a double fold. Stitch close to the inside edge.
Use this method to attach a sheet designed for this purpose, like Martha’s antique linen one. Sew buttons, at places corresponding with the buttonholes on sheet, around three edges of the underside of the duvet cover and several inches from the cover’s topmost edge; attach.
Green damask available at local fabric-supply stores.
Cobblefield plaid at Ralph Lauren Home, 212-642-8700 for store locations.