The last step. Selina had just one thing left to do and then she was done dealing with fire. As much as she liked Professor Bentley she did not understand why she had to deal with flammable substances. Eh, she was not the Professor and Bentley knew what she was doing. So she drew her wand and watered the plant with "Aguamenti!"

Simultaneously heated up the water with the spell they had all learned, "Chaundensis!". It was hot!!! Oh Merlin. Once the plant was watered enough she stopped and finished up her work.