In a small bowl, combine the parsley, garlic, rosemary, thyme and lavender. Spread the lamb on a work surface, boned side up and season generously with salt and pepper. Spread half of the herb mixture over the lamb and roll it into a roast. Tie the lamb with kitchen string at 1-inch intervals. Spread the remaining herb mixture all over the outside of the roast and season with salt and pepper. Let the roast stand at room temperature for 1 hour.