How to Whiten Curtains

When you first hang them up, white curtains make a space look lighter and brighter. It doesn't take long for white draperies to take on a dingy or yellowish tint though — especially when they're hung in windows that get a great deal of direct sunlight or if anyone smokes in the home. Using bleach is the easiest way to restore white curtains to their former glory, assuming they're made of durable fabric.

Fabric type is always an important factor when you're finding the best way to care for white curtains. A whitening method that's safe for cotton might cause damage to delicate lace or even silk curtains. Because even one stain or tear can destroy the appearance of your curtains, erring on the side of caution is always the best strategy here.

Look for a cleaning tag, which may be hidden along a seam on the back side of the curtains or reach out to the manufacturer for suggestions about care and cleaning. This tag won't tell you how to whiten your curtains but should tell you whether the fabric can be machine washed and whether they're safe to use with bleach.

If you can't get specific cleaning guidance from the manufacturer, you may want to start by cleaning and drying just a small corner of the fabric before washing the entire panel. Skip home cleaning altogether if your curtains are made of wool or a delicate fabric like silk or brocade or if they're adorned with beading or other embellishments. Entrust these fabrics to an experienced dry cleaner.

People commonly use bleach to brighten white clothing or even to bleach fabric white, so it may be the first product you think of when you're trying to whiten curtains. A key advantage of chlorine bleach is that it's safe for use with a lot of common and durable fabrics including cotton, polyester, and linen. You can use it to whiten white towels and brighten white curtains as long as they're not made of a more delicate fabric like lace.

The alternative is oxygen bleach, also called nonchlorine bleach. It's generally safe for use on any machine-washable fabrics, including colored fabrics and those made with spandex. Curtain panels rarely include spandex and you're not worried about color transfer with your white curtains, but some curtain fabrics may be treated with a kind of finish that will turn yellow when exposed to chlorine bleach. If your white curtains have a cleaning tag that says "nonchlorine bleach only," use oxygen bleach to whiten them.

Always dilute bleach with water before letting it touch the fabric. For best results, start by soaking curtains in a solution of 1/4 cup bleach per gallon of warm water. After about 10 minutes of soaking, wash curtains in the washing machine with hot water, regular detergent, and about 3/4 cup of bleach. (If your machine doesn't have a bleach dispenser, start the water and mix in the bleach before transferring the curtains to the washer rather than pouring pure bleach over the fabric.) If you'd rather not handle liquid bleach, dissolve bleach tablets in water to get the same effect.

What if you'd prefer not to handle bleach at all? Unless the manufacturer warns otherwise, it's generally safe to use the same products on the curtains that you'd use to brighten white clothing. A product called bluing liquid can be highly effective at whitening fabrics that have started to turn yellow or gray in appearance. Follow package directions to whiten curtains with bluing liquid. Or add 1 cup of hydrogen peroxide to the hot water and detergent before machine washing your curtains.