Deep cleaning is an important part of keeping your dreadlocks clean, fresh and happy, and happy dreadlocks lead to happy dreadheads - but this often leads to the question of 'when to deep clean dreads?'.
How to deep clean: https://www.youtube.com/watch?v=X782R85mFJE
Just how there is no simple one-size-fits-all answer for when you should wash your dreadlocks, the same goes for a deep clean. The straight forward, blunt, but at the same time not all that helpful answer is that they should be deep cleaned when they need deep cleaning.
I personally deep clean my hair every 1-2 months, so on average, every 6 weeks. I do not stick strictly to this schedule, if my hair needs deep cleaning in the meantime, I will not hesitate, but I find that soaking them every 6 weeks or so allows me to stay well ahead of most issues that can arise and that frequency keeps my hair happy - it's a decent balance between keeping the dreads fresh... and not spending every weekend with my hair in a bucket.
Some people may find their dreadlocks benefit from being deep cleaned more or less frequently as different environments, climates, water hardnesses and regular soaps will all play a role. Overtime you will begin to be able to tell when your hair needs deep cleaning.
If you've never deep cleaned your hair before, it's never too late to start, but some will ask whether it can be too soon. Generally young dreadlocks do not need to be deep cleaned. Young dreadlocks should not yet have had time to accumulate soap residues and will generally rinse quicker than older, denser dreads, so will take longer for build up to... build up, but a deep clean can sometimes be welcomed for treating irritated scalps or removing the residue from an inappropriate soap. A deep clean will strip away anything left within the dread, leaving just clean hair behind that is primed for knotting, so some people will find the benefit from deep cleaning even younger dreads: however if you plan on deep cleaning younger dreads you will need to be cautious with the use of the conditioning/moisturising/softening ingredients: ACV, essential oils, as these may be too softening for use on already soft, young dreads.