Heat oven to 200º. Cut apples lengthwise from stem end through core into 1/4-inch slices. Dip apples into lemon juice to prevent browning; place on wire racks. Carefully place wire racks on oven rack. Bake 3 1/2 hours. Turn off oven; leave apples in oven 8 hours or overnight.
Place dried apples on waxed paper. Coat each side with 2 light coats of spray varnish, following manufacturer's directions.
Tie 10-inch cinnamon sticks together with florist wire. Attach to front of wreath with 6 inches of the ribbon. Glue dried apple slices and 3 1/2-inch cinnamon sticks to front and side of wreath, using glue gun. Attach leaves to ribbon on 10-inch cinnamon sticks. Make a bow with remaining ribbon, and attach to wreath. Attach wire hanger.