Stuff the cavity of the chicken with fresh rosemary, the cubed orange, and some of the onion slices and garlic cloves. Tie the drumsticks together with kitchen twine.
Make a ring of foil by rolling 2 large pieces of foil into tubes and connecting them to form a ring. Place it in the bottom of the crockpot.
Add the potatoes, carrots, the rest of the onions and garlic, and more fresh rosemary to the center of the ring.
Mix the dry seasonings in a small bowl. Then, coat the top of the chicken with garlic olive oil and add the seasoning mixture.
Pour the chicken broth over the vegetables. Then, top them with the whole chicken. Add a few more sprigs of rosemary to the top of the chicken.
Cover and cook on high for 3.5 to 4 hours or on low for 5 to 6.5 hours until the temperature registers 165 in the thickest part of the breast.
Place the crockpot vessel (NOT the whole crockpot) in the oven and roast at 400 for 5 to 10 minutes to get a nice, crispy skin if you like.