- 1). Put on work gloves to protect your hands. Add a handful each of dry sand and gravel into powdered concrete. Mix together. This will provide stability and prevent posts from breaking off in the future.
- 2). Dig a hole at least 17.5 inches deep for each post. Fill the hole halfway with water and place the concrete mix on top. Add enough water to fill the hole to ground level if the powder is still dry.
- 3). Insert the post into the wet concrete. Using a trowel, mound the concrete around the base of the post (at ground level) to allow water to run off. Occasionally poke the concrete to eliminate air bubbles.
- 4). Work as fast as you can, as the concrete will set in a few minutes. Use a spirit level to make sure that the fence post is upright on two adjoining sides. Use the fence line as a guide. Be certain the posts are secured and are in line with each other.
- 5). Let the concrete dry and harden completely (about 24 hours) before continuing with construction.
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