Soak bamboo skewers in warm water for at least 30 minutes and for up to 3 hours. Make sure the skewers are fully submerged.
Peel fresh shrimp, leaving the tail on (optional).
Prepare marinade by combining olive oil, lemon juice, lemon zest, garlic, parsley, salt, and pepper. Reserve 1/4 cup.
In two separate bowls combine seafood and veggies with marinade. Let it stand for 15-20 minutes.
Alternately skewer shrimp, scallops, and veggies in a pattern of your choice.
Heat a large grill pan. Grill, turning every few minutes until shrimp turns pink and scallops are opaque, approximately 8 minutes.
Drizzle the reserved marinade over skewers and serve.