• 1/2 cup cider vinegar
• 1 cup water
• 1/2 cup sugar, to taste
• 1 tablespoon poppy seeds
• 1 serving salt and pepper to taste
• 1 bunch scallions, trimmed and chopped
• 3 cups seedless watermelon balls or small chunks
• 2 English cucumbers, peeled, seeded and sliced into small slices

Mix together the vinegar, water, sugar (adjusting as desired) and poppy seeds in a bowl and season with salt and pepper to taste. Stir in the chopped scallions. Place the watermelon and cucumber in a serving bowl and pour the marinade over the top. Serve immediately or cover and refrigerate a couple of hours before serving. Toss gently before serving.

Source:

Watermelon.org