One of the first steps in cleaning any carpet is determining what made the stain in question. By doing this you can choose a method that will best remove the stain. If you don't know what caused the stain, you will have to troubleshoot the cleaning process and try several different cleaning solutions to find one that is most effective. Artificial coloring in beverages or grape juice are often the causes of purple stains on carpets.
Things You'll Need
Liquid dish soap
Distilled white vinegar
Mix 1/4 tsp. liquid dish soap with 1 cup warm water. Do not use dish soap that has bleach or strong coloring in it, as this could do more damage to your carpet.
Brush the soapy solution into the purple stain with a toothbrush. Be careful not to brush too hard, as this could work the stain deeper into the carpet or could spread it further.
Mix 1 cup distilled white vinegar with 2 cups water if the stain is still visible.
Dip a toothbrush into the vinegar solution then apply the solution to the stain.
Mix 1 tbsp. ammonia with 1 cup warm water. Ammonia is especially effective in removing fruit juices.
Dip a toothbrush into the ammonia solution and scrub away the stain.
Press a cloth into the area to soak up all of the excess cleaning solution.
Mist the area with clear water from a spray bottle. This will help rinse away the cleaning solution residue.
Soak up all of the excess cleaning solution and water with a clean cloth.
Continue misting and drying the carpet until you've rinsed all of the cleaning solution. A slight vinegar smell might remain, but it will dissipate eventually.
Do not scrub the stain, as this can damage the carpet's fibers.