Mix together 3/4 cup all-purpose flour, the rye and bread flours, salt, yeast, and warm water in a large bowl with a wooden spoon. (Dough will be sticky.) Cover bowl with a kitchen towel and let rise in a warm place until doubled in size, 2 to 2 1/2 hours. Refrigerate dough in bowl until cold, about 1 hour.
Preheat oven to 475 degrees, with a pizza stone or inverted rimmed baking sheet on rack in top position and a metal baking pan on rack in lowest position. Transfer dough to a lightly floured work surface and sprinkle with remaining 1/4 cup all-purpose flour. Knead briefly to incorporate, then form into a smooth ball. Return to bowl, cover with towel, and refrigerate 30 minutes.
Invert a cookie sheet, cover with parchment, and dust with all-purpose flour. Place dough in center. Poke a hole in center of dough with your thumbs and stretch it until dough measures 9 inches in diameter and hole measures 4 1/2 inches in diameter. Generously sprinkle with all-purpose flour and let rest, uncovered, 15 minutes. Using kitchen shears, cut 14 deep Vs into top of dough, going almost all of the way through. Pull points of cut Vs away from center to create 14 leaves around wreath. Let rest, uncovered, 15 minutes.
In one quick motion, slide wreath on parchment onto pizza stone, then pour water into metal baking pan. Bake until bread is golden brown, about 20 minutes. Slide wreath on parchment onto a baking sheet, then slide wreath off parchment onto a wire rack. Let cool at least 30 minutes before serving. Bread is best eaten same day it is made.