Preheat oven to 400°F. Line a baking sheet with parchment paper. Slice off corn kernels and spread on baking sheet. Roast till soft and starting to brown, around 20 minutes. Let cool completely.

Pour the milk, sugar, lavender, vanilla, and salt into a saucepan. Heat and stir until sugar is completely dissolved—do not boil. Remove from heat and let steep for 30 minutes, covered. Strain out lavender. Pour into a blender and add corn. Puree till smooth; strain and discard corn pulp. Pour mixture into popsicle molds and freeze.