Preheat the grill to medium-high.

Cut 4 large pieces of foil and set aside.

In a large bowl, combine the halved potatoes with olive oil, garlic powder, thyme, rosemary, salt, and pepper.

Divide the potatoes between the foils.

Fold the sides of the foil over the potatoes, covering them completely; seal the packets closed.

Place the foil packets on the grill and cook until tender, about 20 to 30 minutes, turning once. Pierce with a fork to check for doneness.

Remove from grill and carefully open up each packet.

Sprinkle with parsley and serve.