Place the watermelon cubes, blueberries, and jicama in a salad bowl. Sprinkle with lime zest.
Whisk together the lime juice and honey, then season with salt. Gently toss the dressing into the salad.
Finally toss in the feta cheese and serve immediately.
NOTES: The watermelon will release its juices over time and makes the bottom of the bowl soupy. If making ahead, you may need to pour off the juices after an hour. You can also mix everything but the watermelon. Cut the melon and place them in a separate bowl. Then add the watermelon chunks into the salad right before serving, leaving the juices in their own bowl.