There's an interview up on Vogue.com with Polachek where these very questions are addressed. Turns out, splashlights grow in marvelously, becoming "softer and more natural looking." And, to maintain the look while it grows in, Polachek's stylist doesn't re-bleach the stripe. Instead, he dyes the dark hair surrounding it with a darker shade of brown. This allows her to maintain the contrast between the two colors, without damaging her hair by constantly bleaching the same part.
We're not sure if Polachek was just blessed with good genes, but it seems that her splashlight has maintained a perfectly horizontal line as it grows from her ears to her collarbone. Eventually, this will look like bleached tips until the splash grows out completely.
So, we're wondering if the splashlight's journey down Polachek's mane is an allegory for the shelf life of the trend itself. Once it grows out, will it be gone for good? (Vogue.com)
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