This depends on many things such as whether you have animals inside regularly, also whether your husband and children take off their shoes at the door and how many mats you have to scrape off the dirt.
I would advise you to have them cleaned at least twice a year to remove fine soil and oily soils a vacuum just does not remove.
You may find this article helpful in further answering your question. http://www.cleanfax.com/carpet-cleaning/article/cleaning-frequency
Or give Craig or Beate a call for your Riverland carpet cleaning needs on 85 84 51 56 or 0429 845156.
Or feel free to look at our website www.craigscleaningservice.com