Root touch up used to be a secret. In 1956, Shirley Polykoff, a copywriter at Foote, Cone & Belding, wrote the line "Does she or doesn't she" for Miss Clairol, the at-home hair color, and followed it with "Only her hairdresser knows for sure." Malcolm Gladwell told the story in The New Yorker, including that Clairol bought thirteen ad pages in Life that fall and Miss Clairol took off. The idea was that coloring your hair could be private and normal at the same time.

That is still what a root touch up is for. Regrowth shows first at the part and the hairline, and grays show more than anything else, usually weeks before you want to book a full color.

There are two ways to handle it. Temporary cover-ups, meaning powders, sprays and sticks, sit on the hair and wash out with your next shampoo. They take seconds and there is no commitment. Permanent root kits dye only the regrowth, cover grays fully and last until the hair grows again, and most take about ten minutes.

The first grid is instant cover-ups. The second is at-home root color kits plus two quick fixes. My tip: choose a cover-up a touch lighter than you think, apply it to dry hair along the part and hairline only, and let sprays dry completely before you touch them.

Clairol Temporary Root Powder is the most reviewed product in this edit by a wide margin. It is a compact powder that covers grays on the go, and it is the one I would keep in a bag. Color Wow Root Coverup is the powder people usually mean, an allure Best of Beauty winner that covers grays and dark roots, extends highlights and fills in a thinning part with no waxes or dyes. Madison Reed The Great Cover Up is a brush-on powder for roots and brows that stays through rain, sweat and your pillow until the next shampoo.

For sprays, L'Oréal Paris Root Cover Up covers grays in seconds with no ammonia or peroxide. IGK Never Miss is transfer-resistant and waterproof, washes out after one shampoo, and has the best rating in this grid. Oribe Airbrush Root Touch-Up Spray dries fast with microfine pigments and adds UV protection.

Bumble and bumble Color Stick is a dry-fiber stick for small patches of gray, and the Bumble and bumble Brownish Tinted Dry Shampoo cleans the roots and tints them at the same time, which is useful on day two.

What I would skip: a spray on wet or damp hair. It streaks and transfers onto collars and pillows. Use it on dry hair and let it set before you brush through.

Garnier Color Sensation Color Retouch is the most reviewed and best-rated kit in this grid. It is ammonia-free and demi-permanent, you mix it in your hands, and it gives up to four weeks of root coverage and up to 100 percent gray coverage in ten minutes.

Clairol Root Touch-Up Permanent Hair Color comes in 28 shades with a bowl and brush, for full gray coverage in about ten minutes. Clairol Total Root Touch-Up adds a color mask for the lengths, so the ends match the new roots. L'Oréal Paris Magic Root Rescue is a ten-minute permanent kit made to match salon color. Madison Reed Root Perfection has two applications, each with a color cream, an activator and a hair mask. dpHUE Root Touch Up Kit is permanent and made for up to an inch of new gray at the part and hairline.

The two quick fixes are for the days between kits. dpHUE Color Touch-Up Spray dries quickly and lasts until your next shampoo, and L'Oréal Paris Magic Root Precision is a small brush for fine, scattered grays.

What I would skip: pulling a permanent kit through your lengths every time. Color only the regrowth and use a mask or gloss on the ends, or they will get darker and drier with every round.

I think the best root touch up routine is a mix of both. Keep a temporary powder or spray for the week before a color appointment or an event, and use a permanent kit when regrowth passes the point a powder can hide. Choose a shade slightly lighter than your color, work only on the part and hairline, and leave your lengths alone. Miss Clairol made home color normal in 1956, and the goal is the same now: no one needs to know.