Make the salad: In a large bowl, whisk to combine oil, vinegar, mustard, salt, and pepper. Add pepper cress, pea shoots, flowers, and beets, but do not toss to coat. Set aside.
Prepare the peas and radishes: Bring a small saucepan of water to a boil. Add peas, and blanch for 2 minutes. With a slotted spoon, remove from pot, and set aside. Blanch radishes for 2 minutes, and add to snap peas. Melt 2 tablespoons of butter in a medium skillet over medium heat. Add 1 tablespoon water, the peas, and radishes. Cook until water evaporates and butter coats vegetables, about 2 1/2 minutes. Season with salt and pepper.
Meanwhile, cook the scallops: Heat a large nonstick skillet over medium-high heat. Season scallops with salt. Working in batches if necessary so as not to crowd pan, sear scallops until golden brown, 2 to 3 minutes per side. Transfer to a platter to keep warm. Season second side with salt and pepper. To the hot pan, add remaining 2 tablespoons butter and the orange zest and juice. Cook until butter is melted and flavors are combined, about 1 minute. Pour sauce over scallops.
Toss the salad. Arrange scallops, salad, and sauteed vegetables on dinner plates. Garnish with chive flowers, if desired. Serve immediately.