Patchouli Culture and Oil Extraction

I just bought 2 patchouli plants and no one seems to know exactly how to grow and care for them. I would like to know this and also when and how do I go about extracting oil from the plant?

Patchouli plants like rich, moist soil with high humidity and a minimum temperature of 16 to 18 degrees Celsius (61 to 64 degrees Fahrenheit). They like sun to half shade. The plants grow 1 meter tall and wide.
The leaves are harvested by cutting the plants' top third off, two or three times per year. The leaves can be dried, but fresh leaves yield a better oil.
To distill the oil, place the leaves in a stainless steel or other inert colander, place the colander over, not in, boiling water and collect the steam in a glass vessel with external cold water cooling. The condensing steam will contain the oil. The latter can be skimmed off the cooling liquid.