Product Recommendation Request

We just replaced the floor of our covered porch with tongue and groove red pine. I live in Ontario where the temperature can vary drastically between summer and winter and we also receive a great deal of snow. Although the porch floor is covered, precipitation can accumulate, although we remove it fairly quickly. The porch will have heavy traffic as it is the main entrance to the house, so I am worried about wear on the boards from boots and salt. We are considering a semi-transparent product and are wondering :
How long do we wait before staining/sealing the wood? A couple of months? Or a full year?
What product would be best to use for the type of wood and our weather conditions?