Over time, your teak wood instead, from its original golden brown color it becomes a silver gray.
During this period of transition, you can observe an oxidation that is nothing more than an effect caused by the superficial oils of the wood in contact with humidity and air (fog, dew).
This is a normal stage of teak, and also of most woods, but if we take measures in time they can be easily corrected.
As with everything left outside, its cover will be subject to impurities in the air, such as pollen and air dirt or pollution. For this, we recommend washing, wet frequently without any additive, soap or of course degreasers. Teak loves water.
Occasionally perform this same process with soapy water, but use a very mild neutral soap, this will help keep air impurities out of your cover.
Difficult spots can be a sponge with soap and water. Punctual application of a cleaner may be required.