Cut the artichokes in half and scoop out the fluffy choke on the inside. Immediately brush some lemon juice across the inside and cut flesh to prevent browning. Repeat with the other 3 halves.
Smash the garlic cloves and in a small bowl mix the rosemary, thyme, garlic and lemon zest. scoop equal amounts into the cavity of the artichokes and brush with half of the olive oil. Season the cut halves of the artichokes with half of the salt and pepper.
Place the artichokes cut side down in the baking dish and brush the remaining olive oil on outside and sprinkle with the remaining salt and pepper.
Cover with aluminum foil and bake for 30 minutes. Remove the foil and continue to roast for an additional 15 minutes or until the outside starts to crisp up.