1. Jump to the right below the bird. Make it drop a bomb at the shown position.
2. Go to the left again. Go for another bomb at the same position.
3. Go below the green blocks. The room is easier to solve from this position. Stay under the 4th block from the left. Wait until the bird drops three bombs on this position. You can hide under the leftmost block if you don't want the bird to drop a bomb.
4. Now the ladybug can walk to the four cacti surrounding the color switch.