I was given a bunch of young Garden Phlox yesterday, but I am worried they are too small to survive a Long Island winter.

Does anyone know how big these plants would need to be to make it? Is there even a rule of thumb for this? I would think that a zone hardy perennial would be somewhat safe if it had the entire spring & summer to develop, but I believe these were probably started early summer. (they have no real "stem" yet, but about 4-5 developed leaves on each one that are fully out of the ground)

Unfortunately I don't have a good setup in my home right now to be able to bring anything inside for the winter, or else I would just plan to do that.

Do I write them off as a lost cause (*sigh* that would suck) or is there something I can do to try to help them make it through?

Any input from more experienced people out there would be very helpful!