On preservation of your fence, you might want to think of painting your fence every three years depending upon your environment. Now, touch up as needed. Make sure that you save a sample of the original paint. When you do your touch up, the paint will match and it will look very lovely. Now if you find that your fence is looking a little dingy in between your paintings, you can easily get a pressure washer and pressure wash your fence to return it to your like-new condition. Another helpful tip in preserving your picket fence, is to remove the dirt or any wet debris at the bottom of your fence. You wanna keep your bottom of your picket fence as dry as you possibly can in order to prevent rot. When you paint a fence, it has two primary functions. The first is that it looks good. But the second is that it helps to preserve the wood to keep the outside from coming in. Now, we used a soft wood here, which is pine. If you use a harder wood, maybe one coat of primer, one coat of paint will suffice. Being the fact that this is a softer wood, we put on one coat of primer and two coats of paint.