Do not scrub, that's the fastest way to scour deep furrows into the wood and have it deteriorate sooner.
have used a British made product, a 2 pack teak cleaner and conditioner made by Wessex Chemical Factors, just google that for details. Simply wet the timber a section at a time, then simply dilute part A and sponge on with a swirling motion to bring up any dirt, leave for a few minutes and swirl again, then liberally hose off with fresh water... the teak comes up a golden colour. Then similarly apply diluted part B, the conditioner, leave for a few minutes and again hose off. The results are truly remarkable and removes oil and red wine stains, with no damage to the 2001 timber.