Wash the potatoes thoroughly and cook for 15-20 minutes. Drain and allow to cool.
Wash the herbs, dab dry. Remove approx. 18 large sage leaves and wrap them around 18 potatoes. Put 3 on 1 skewer each. Skewer the remaining potatoes on rosemary twigs.
Brush the potato skewers with oil and sprinkle with coarse salt. Grill on the hot grill, possibly on grill trays, for 10-12 minutes.