- 1). Test the concrete planter to make sure that it will absorb stain. Take a small amount of water and drizzle it on the planter. If the water rolls off, then the planter has been treated to prevent water from penetrating it, which means the stain won't adhere. Apply stripping agents with a sponge and scrub the surface with the wall scraper and scrubbing brush to remove any debris and sealant on the concrete. Use stripping agents that will mix with water. Follow the manufacturer's instructions on the stripper to remove the sealant.
- 2). To smooth the surface of the planter, use your diamond pad and gently scrub the planter with small circular motions. This will help remove any blemishes on the planter's surface.
- 3). Sand the surface of the planter with the sandpaper.
- 4). Apply the stain to the concrete planter with a paintbrush. Some stains require you to mix the stain with water while some do not. Follow the manufacturer's instructions for the stain directions and drying time specific to the product you are using.
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