Every Mill has their own specific suggestions regarding care and maintenance and it is important to follow their recommendations so as to not negatively effect any warranties...
Here are some links to help:
Godfrey Hirst Care & Maintenance Guide
Signature Carpet Maintenance Manual
Provenza Maintenance - Residential
Provenza Maintenance - Commercial
Provenza Maintenance - Oil Finish Products
All Wool Carpet Care...
Wools Of New Zealand Carpet Care