Soak 4-5 bamboo skewers in cold water for at least 30 minutes. (You can soak them right before your start. The whole cooking process is going to take longer than 30 minutes.) Soak 5 dried edible sakura blossoms in cold water for 15 minutes. Rinse and pat dry the soaked sakura blossoms with a paper towel. Carefully remove the stem, finely chop or crush the petals into mud texture.
Add 1 cup of glutinous rice flour, ½ cup of rice flour, ½ cup of powdered sugar, and ½ cup cold milk, soy milk, or water in a large bowl. Use clean hands to combine all the ingredients and knead them into a smooth dough. (Add 1 to 3 extra tbsps of milk/water if the dough feels too dry or fall apart.)
Divide the dango dough into 3 equal pieces. Add crushed sakura petals to one piece of the dough, add 1/2 tsp of matcha powder to another piece of the dough.
Optionally add 1 drop of red food coloring to the sakura dango dough for a pinker color.
Knead each piece of the dough until the color is evenly distributed.
Divide each dough in different colors into 4 equal pieces, roll into round balls. Each dango ball should weigh about 28g. (If you prefer smaller dango balls, you can make 5 balls in each color, then each dango ball should be about 22g.) This recipe will make 12 large balls, or 15 smaller balls in total.
Bring a pot of water to a boil. Boil tricolor dango balls over medium heat for about 15 minutes or until floating. (You can optionally boil them in separate batches in the order of white, pink, and green. I tried to boil all the tricolor dango balls together in a large pot. The white dango balls weren't dyed by the other colorful dangos. So it's fine to boil them all together.)
Use a slotted spoon to transfer the cooked tricolor dango balls to a large bowl filled with ice water.
Insert cooled dango balls onto a bamboo skewer in the order of green, white, then pink.
Optionally serve with brown sugar syrup drizzle. (See my warabi mochi recipe for how to make brown sugar syrup easily at home.)