The key is to read…the information that came with your furniture, and the information that is on the tin. Like one brand says, “it does exactly what is says on the tin.”
Always try to ensure that you keep on top of the treatment that is needed for it, i.e. once a year, or once every 3 years. Usually it is a good idea to treat the furniture as soon as possible after purchase (unless you are specifically told otherwise).
All cut wood, no matter if it is soft wood, hard wood, oak or birch will turn a silver/grey colour in time if it is left untreated. It is the UV rays that make this happen, therefore when choosing your preferred treatment look for one with a good pigment in as this will help to prevent this from happening.
Don’t forget the feet of your chairs, benches and tables need protecting too! Give the bottom of your furniture a good 2/3 coats of your treatment, as this will help reduce the amount of moisture soaked up when standing in damp conditions, therefore reducing the risk of the wood rotting.
One last thing, keep a note of the treatment you used and the colour so that when you need to buy another, you know exactly which one will match.