Trim the rhubarb, discard any leaves, and cut the stalks into 2 cm / 3/4-inch pieces. Zest the orange, then juice it. Grate the ginger finely.
Add the rhubarb, maple syrup, orange zest, orange juice, ginger, and salt to a 3-quart / 2.8 L saucepan. Set over medium heat and bring to a gentle simmer, about 4 minutes, stirring once or twice.
Lower the heat to medium-low and simmer for 8 to 10 minutes, stirring now and then, until the rhubarb is soft and most pieces still hold a rounded edge. Stir in 1/2 tsp vanilla and take the pan off the heat. Taste, and add an extra teaspoon of maple syrup only if it's too sharp.
While the compote cools slightly, whip the cold cream and 1/2 tsp vanilla in a 1.5-quart / 1.4 L bowl for about 2 minutes, until soft peaks form and the cream still slumps off the spoon.
Spoon the compote into 6 small glasses or bowls, about 1/3 cup / 100 g each, and top with 2 tbsp / 30 ml of cream. Serve warm or chilled.