You can get either a water-based or an oil-based fence stain. If you choose the former, you’ll notice that it takes much less time to dry. Some of the water-based stains include very small amounts of zinc. This helps to prevent mildew and mold from forming on the wood.
Water-based fence stains are non-flammable and will not give out any toxic fumes. Some of them will last longer than oil-based stains. However, water-based stains need a proper primer of the fence before you can apply it.
Oil-based stain types are easier to apply and give a smoother finish. They also go deeper into the fence and preserve it well. Such stains take up to two days to dry. Plus, they are flammable and give out toxic fumes, thus requires caution. Moreover, mold likes to feed on oil-based stains.