Rose of Sharon

Personally I'd harden them off now and start pinching them back next Spring, cos if you pinch them back now they may make soft frostable growth and you could lose them - but someone may know different.

Well done for rooting these... they will soon romp away in the spring to make a good clump.

As others said, harden them off now, as then they will be fine outside all winter.

If you are keeping them in pots though don't let them freeze --- best in the ground, planted out around October time. The soil will still be warm (ish) then and they should have strong roots by then too