Your handy guide to rainbow roots, the hair trend dominating Instagram.

Hair trends come as fast as they go, but the latest big thing is one we can’t stop staring at.

Called ‘Rainbow Roots’, it sees a myriad of colours applied to the roots of the hair, really close to the scalp, so that when the wind blows the rainbow is exposed.

According to Karen, hairdresser and co-founder of the popular salon Blondies of Melbourne, the trend is really taking off. Recently, an Instagram video of  one of her client’s rainbow roots hit 100,000 views in under 24 hours:

Tie dye rainbow roots @helloitsaylin is shaving her hair TOMORROW to raise money for the leukaemia foundation, if you can help please follow the link to donate https://secure.leukaemiafoundation.org.au/registrantFundraisingPage.aspx?RegistrationID=658879 . . . . @behindthechair_com #behindthechair @modernsalon #modernsalon @esteticausa #esteticalikes

A post shared by Blondies Of Melbourne (@blondieshair) on Mar 11, 2017 at 2:08pm PST

So what’s it all about? We get Karen to break it down for us a little bit.

Ok, let’s start with the process. What’s involved?

Sorry, brunettes, but rainbow roots needs to be applied to pre-lightened blonde hair.

“Once your hair is blonde it’s pretty simple,” Karen explains.

“The vibrant colours are applied in an alternating pattern, the process takes about 30 mins and voila: rainbow roots!”

But what if I’ve got brown hair, can I get it done too?

Again, for brunettes who are interested in trying the look, the roots have to be lightened first. But don’t be put off by that.

“With great products like Olaplex these days, bleach is nothing to be afraid of,” Karen says.

“Plus, a bit of bleach at your roots means you don’t have to wash your hair as often and will give your hair body and volume. So, really, everyone should be putting bleach their hair.”

Is it any different to rainbow hair?

Yes, absolutely. Because it's only applied to the roots of the hair, this trend is a little different to your everyday rainbow hair, meaning "it's a lot softer" and "less in your face", according to Karen.

"It can be a subtle, hidden rainbow painted closer to the scalp, or stretched out further through the mid lengths of the hair to show more of the rainbow off."

Listen: What you need to know about hair dye and pregnancy. (Post continues after audio.)

What kinds of hair (and people, even) is it best suited to?

Karen believes those with a "hidden wild streak" are best suited to dabbling in the bold colour.

After all, it's conservative at first, "with flashes of rainbow in the wind".

Does it last long?

This totally depends on how often someone will wash their hair, what kind of products they're using, and the shades involved.

"Vibrant colours always hold much longer than pastels as they have more pigment in them," Karen explains.

"As with all hair colour its very important to use salon quality products prescribed by your hairdresser when washing as this will preserve your colour, while being best-suited to your hair type."

A secret little tip to prolonging colour? Wash your hair in cold water, says Karen. It will stop the colours from leaking on to each other.

Is rainbow hair just here to stay now?

"I think it has become a lot more accepted for people to have non-natural coloured hair in the workplace, so definitely more popular, and very addictive," Karen says.

An added benefit of coloured hair, she believes, is that they slowly "evolve" into lighter shades before fading to blonde, meaning "you constantly have people coming up to you asking if you have had your hair coloured again."

New hair with no effort? That's something we can get on board with.