Toast nuts in a small pan over medium heat, 3 to 4 minutes, then let them cool.
Combine chopped lettuce, beets, radishes, onion, celery and toasted walnuts in a shallow bowl. Place the preserves into a small bowl and whisk vinegar into it. Add poppy seeds to dressing if you are using them. Whisk extra-virgin olive oil into the dressing and season it with salt and pepper. Dress salad and toss to coat evenly then adjust salt and pepper to your taste.