Smooth wood needs to weather 4-12 months, so at 4 months you are at the very early end of that window. Prep with the Gemini Restore A Deck Kit and then test a small area — if the stain soaks in within a few minutes it is ready, and if it sits on the surface the wood needs more time. Either way it is one coat only on new smooth wood, back wiping anything that has not penetrated after 30 minutes.
My fence is new, built 4 months ago. It’s pressure treated pine. Should I use just 1 coat of 1500 stain or 2?
Rough-sawn cut wood or smooth wood?
Smooth wood
Smooth wood needs to weather 4-12 months, so at 4 months you are at the very early end of that window. Prep with the Gemini Restore A Deck Kit and then test a small area — if the stain soaks in within a few minutes it is ready, and if it sits on the surface the wood needs more time. Either way it is one coat only on new smooth wood, back wiping anything that has not penetrated after 30 minutes.
https://www.twpstainhelp.com/prepping-new-wood-for-twp-stains/