Preheat the Traeger Grill to 400F.
Prepare the asparagus by washing and removing bottom 1-2 inches depending on the thickness of the asparagus. The bigger the asparagus, the more you'll need to trim. For really big asparagus stalks, use a vegetable peeler to peel the bottom 2 inches.
After the asparagus is prepared, drizzle the stalks with olive oil. Season them with salt, pepper, and granulated garlic. Make sure they are evenly coated on all sides.
Once the grill has reached 400F, lay the asparagus on the grates in a perpendicular direction so they do not fall through the grates. You can also use a vegetable grill pan to make sure they stay on the grill.
Cook the asparagus wit the grill lid closed for 8-10 minutes. Poke the asparagus with a fork to check for doneness. When the asparagus is cooked but has a crunch in the center, it is ready to remove.
Use tongs to pull the asparagus off the grill onto a serving plate. Squeeze with the lemon juice from half of a lemon and serve.