Wash and dry all fresh ingredients. Thinly slice the celery, core and dice the green apples, and cut the cucumber into half-moons. Finely chop the red onion and dill.

In a medium bowl, combine lemon juice and zest, then add the olive oil. Whisk in salt, sugar, and black pepper until well combined.

In a large salad bowl, combine the celery, cucumber, green apples, red onion, and dill. Pour the dressing over the salad and toss gently.

Let the salad rest for about 10-15 minutes at room temperature.

Serve the salad chilled or at room temperature.