Rum Punch with Passion Fruit and Lime


1 1/2 cups gold rum
1 11.5-ounce can frozen passion fruit juice concentrate (such as Welch's)
1 cup water
1/3 cup fresh lime juice
3/4 teaspoon fresh ginger
4 pineapple spears
Ice cubes
Fresh mint sprigs

Mix first 5 ingredients in pitcher until concentrate dissolves. Place 1 pineapple spear in each of 4 tall glasses; fill glasses with ice. Pour punch over ice, garnish with mint, and serve.