Preheat your grill or grill pan to medium-high heat.
In a small bowl, whisk together 1 teaspoon of olive oil, lemon juice, lemon zest, dill, parsley, garlic powder, salt, and pepper to create the marinade.
Brush the salmon fillet and the asparagus spears with the remaining 0.5 teaspoon of olive oil.
Rub the prepared lemon-herb mixture evenly onto the flesh side of the salmon fillet.
Place the salmon on the grill, skin-side down first, and cook for 4 to 5 minutes without moving it to ensure a crispy skin.
Add the asparagus to the grill alongside the salmon, turning occasionally until the spears are tender and slightly charred.
Flip the salmon carefully and cook for an additional 3 to 4 minutes until the internal temperature reaches 145°F and the fish flakes easily with a fork.
Remove from the heat and let the salmon rest for 2 minutes before serving with the grilled asparagus.