Plain sweet potato stains are pretty simple to remove. Just scrape off the excess potato and then hold the fabric under cold running water to flush out most of the stain. Use a prewash stain remover or a bit of laundry detergent and wash as usual.
The problem comes if the sweet potatoes are mixed with butter or other ingredients or made into fries . Then you must use a stain remover formulated to remove grease - like Shout or Spray 'n Wash. Then launder as usual. If the greasy stain remains, do not put the garment in the dryer. Treat again until stain is gone. Drying the garment will set the stain and make it very difficult to remove.
If the garment is dry clean only, point out and identify the stain to your professional cleaner. If you are using a home dry cleaning kit, be sure to treat the stain with the provided stain remover before putting the garment in the dryer bag.
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