Prepare the dressing in a small bowl, by combining the lemon juice, lime juice, honey, salt, and white pepper. Whisk until the honey dissolves. Drizzle in the olive oil, and whisk together until well combined. Set aside.
In a large bowl, combine the cucumber, tomatoes, spinach, and cilantro. Add in the dressing. Gently fold in the diced avocado. Toss gently and serve immediately.