One inexpensive way to update your home's décor is to change the color of your curtains. Although making light colored fabrics darker is hardly a challenge, attempting to change dark curtains to a lighter hue can seem impossible. Dark colors often streak when bleached, and the coloring ends up uneven. If you expose the fabric to bleach for too long in an effort to even out the coloring, you may damage the fabric. If you are determined to bleach colored curtains, however, you must make preparations beforehand in order to reduce streaking.
Wash and dry the curtains. The curtains should be completely clean before beginning the process of color removal.
Mix 2 gallons of water, the soda ash, the dishwashing liquid, and 1 tbsp. all purpose color remover together into a large pot on the stove.
Add the curtains to the pot and bring the mixture to a low boil.
Allow the curtains to simmer for an hour. Add ¼ tbsp. extra color remover to the pot every 15 minutes.
Drain the pot and rinse the curtains well. The color remover may leave streaking on the curtains, depending on how dark they were initially. This is normal.
Fill a tub or pot with 4 gallons of hot water and the bleach. Allow the curtains to soak in the bleach mixture for several hours. It is important to use oxygen bleach rather than chlorine bleach since soaking fabric in chlorine bleach is more likely to cause damage to the material.
Remove the curtains from the bleach mixture and wash them in the washing machine using a mild detergent. Wring the curtains out and allow them to dry flat or hang them on a clothesline to dry in the sun.
Examine the curtains once they are dry. The original color should be removed and any initial streaking should also have disappeared. Darker curtains may require the process to be repeated several times before the original color will disappear completely.