No, at least 6 months on new wood. Pressure treated takes longer than cedar. There are a few sealants out there that can be applied to green lumber but I've never seen a stain that doesn't recommend a long weathering on new lumber.
That fence is much older than 3 weeks thats for sure.
I prefer to wait 3 months on new pressure treated pine but worst case if someone calls me the day after the carpenter screwed the deck boards down we have a long enough lead time where it does get some drying at least.
You guys must know something I don't. I can't get ready seal to stick very well to new lumber (< 6 months old). It looks too shiny and wears off must faster.
Yea you need something with a drying component (in my opinion) since the newer wood won't accept much of the 100 percent nondrying stains. We use Armstrong but it will still last shorter on new wood but has some drying oil to help out on top. Some people want it done before the wood starts cracking so just have to give them a heads up it may fade more quickly.