Overwintering Patchouli

I bought two patchouli plants from Richters last spring. They were shipped and are doing very well. I have previously bought patchouli and lost them, as they are very sensitive to cold, direct sun and drying out. This time, I have been vigilent and so far so good. We are facing winter and now, what to do once inside... I understand they will lose their leaves and it was suggested to take stem cuttings and make new plants. How do we do this... Also, will the plants return in spring and if they do, how do I care for them during winter. I really love the smell of them and would like to, successfully, keep them around for as long as possible.

Patchouli is a tropical plant and must be over-wintered in doors if you are not living in the tropics. In our greenhouse we over-winter them successfully by keeping them a bit dryer and quite cool say night temperatures of about 10 degrees Celsius and about 15 degrees during the day if the sun does not warm it to a higher temperature on sunny days.
Stem cuttings work much better in early spring, but you can try by giving the cuttings bottom heat. Take a tip cutting of about 5 to 10cm, cutting the stem just below a leaf. Leave it to callus over for about a day, then insert into clean sterilized sand, water, let drain and then place over bottom heat in a fairly bright spot out of the direct sun. Mist every two hours during the day. When the cutting starts to grow, carefully plant it in a pot of Pro-Mix and be sure to not disturb the roots when you do so.