In blender, pulse rose petals and almonds together about 6 to 8 times. Add cardamom, mix through, and lay mixture on large flat plate. With clean hands, remove labneh from cheesecloth and scoop about 1 Tbsp into a ball. Roll to form a small ball about 1 inch in diameter. Drop each ball onto plate with rose petal and almond mixture. Shake plate back and forth a few times, which will move balls through the mixture, coating them at the same time. Repeat with 5 or 6 balls at a time. Remove coated labneh balls to plate; cover and refrigerate until ready to serve.