Yes, that means Im at the salon every four weeks getting a touch-up.

So to make myblondlast till my next appointment, I follow a strict hair routine.

I shampoo only once a week (dry shampoo, I see you!).

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Courtesy of Courtney Leiva

And once its time to give my hair a thorough cleanse, I turn to the best purple shampoos.

Why purple shampoo, you ask?

The color-preserving pigment is a lifesaver for blondes.

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When you look on a color wheel, the opposite of yellow is purple.

These shampoos work because they contain purple pigments, which deposit onto the hair shaft to neutralize unwanted brassiness.

Trust me: Ive been a bottle blonde for over four years, and these picks really work.

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But beware: Use sparingly.

It’s happened to me before.

It works wonders against gnarly yellow roots without saturating the hair with too much color.

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Harsh sulfates can strip your color faster, causing dullness and dryness.

Thats why I love this shampoo.

Its gentle on blond hair color, and it doesnt leave my hair a tangled mess.

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It enhances the vitality of my blond color without leaving my hair dry like a Brillo pad.

I leave it on for two to three minutes, and the toning results are epic.

It really prevents my hair from becoming a brittle heap of straw.

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Thankfully, this shampoo is super gentle.

A good five minutes usually brings back the cool-blond tone I love.

It erases any yellowness because of the hard water in my shower.

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The formula does have a scary purple-black color to it, but its a powerful tool against brassiness.

Its also a summertime essential.

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