In a small saucepan bring honey and 3 tablespoons water to boiling over medium-high, stirring to dissolve sugar.
Boil gently, uncovered, about 3 minutes or until syrupy.
Remove from heat; transfer to a small bowl.
Cool 10 minutes.
Stir in lime zest, lime juice, and ginger. In a very large bowl combine watermelon, jicama, jalapeño, and mint.
Drizzle with syrup; toss to mix. Top with additional fresh mint.