Place the milk and lavender in a small saucepan over medium heat and bring to simmering point.
Remove from heat and allow to cool slightly.
In a mixing bowl, cream the butter and sugar until smooth.
Add the eggs and beat until the mixture is light and fluffy.
In a separate bowl, combine the flour, baking powder and salt; add into the creamed mixture alternately with the milk and lavender and stir until just blended.
Pour into the pan.
Bake for 45 minutes (or till a toothpick comes out clean) in the preheated oven.