There are two distinct ways to deal with the ice flower:

A) Freeze the ice flower by using Grows to bounce its shot back to itself. Then before going to the scritter, set up a Flo bubble with Grow and Pow, to unfreeze the ice flower and to prepare Grows for re-freezing it later.  The bubble will do its thing while you go get the scritter.  Then make the ice flower freeze the scritter on the button, and re-freeze itself.

You need to be somewhat quick to execute this solution successfully, since the Flo bubble and the Grows don't last forever.

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Watch video (Partial solution - this video has the Pow spell take a more roundabout route to the Ice Flower, so it will unfreeze a little later, giving you slightly more safe time to get to the scritter.  But it will leave you a little less time to freeze the scritter and re-freeze the ice flower.)

B) Probably unintended, but it's possible to put a Flo bubble east of the ice flower, which will protect you while you are going to the scritter.  So you won't need to use Grow until after freezing the scritter.

This solution is much easier to execute in terms of speed.

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