This Spring I planted a Tree mallow in the garden: despite being stuck for weeks in a cardboard box in a warehouse somewhere due to the general chaos it lived on and even bloomed, much to my surprise.

It's still a tiny plant, about one foot high, and honestly it hasn't grown that much: it's surely not the "fast growing perennial" I expected.
Temperatures have dropped a lot over the past few weeks here but it still has all its leaves, albeit it looks... not so good right now.

Question is: do I need to do something with it right now or should I leave it alone until Spring? It didn't come with an instruction manual.

Thanks.