Prep the fruit. Rinse and dry everything well. Pat berries dry so they don’t water down the salad.
Cut watermelon, pineapple, mango, and kiwi into bite-size pieces. Halve large grapes.
Mix the dressing. In a small bowl, whisk together honey, lime juice, lime zest, vanilla, and a pinch of salt until smooth. If the honey is thick, warm it slightly so it blends easily.
Combine in a large bowl. Add all the fruit to a big mixing bowl.
Sprinkle the chopped mint over the top.
Toss gently. Pour the dressing over the fruit. Use a large spoon or your hands to gently toss, lifting from the bottom so delicate berries don’t get crushed.
Chill briefly. Cover and refrigerate for 15–30 minutes. This helps the flavors come together and the fruit to chill.
Taste and adjust. Right before serving, taste.
Add a squeeze more lime for brightness, a drizzle more honey for sweetness, or an extra pinch of salt if it needs a lift.
Garnish and serve. Top with a few whole mint leaves and, if you like, a little extra lime zest. Serve cold.