One secret to bright natural fabric whites? Using the sun's rays to disinfect and lighten them.

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Few things say "spring" like a crisp white dress. And few things say "old" like that same dress a few washes later.

Dingy whites are one of the most common wardrobe scourges. It's surprisingly hard to keep clothes truly white, and more than few of us have purchased that dress in the blue to avoid the seemingly inevitable graying of a once-bright, elegant look.

If you've simply been adding bleach to your loads of white clothing, towels and sheets, and wondering why they're not, in fact, white, you probably want to read this. Many people are washing their white clothes in less-than-ideal conditions, and often it takes just a couple of small changes to get back to crisp -- or at least prevent a future white dress from going bad.

Here, some guidelines for washing your whites, including those with colored prints, that should help you get it right. Let's begin with the pure whites so we can get an idea of the white-washing basics.