Tish Cyrus started smoking marijuana after her daughter Miley's tour bus caught fire.

Tish Cyrus

Tish Cyrus

The 53-year-old matriarch admitted she'd never tried the drug until later in life and was always "so against it", until the traumatic incident sparked sleepless nights in her and she sought alternative ways of helping her to relax.

Speaking on E News' 'Daily Pop', Tish - who has a podcast, 'Sorry We're Stoned', with daughter Brandi Cyrus - said: "I was so against it. Like, never in my life had I ever smoked until I was 42.

"But, I was on tour with Miley and she had gone on—we were going from like, Houston to New Orleans—and I stayed behind to meet up with friends and on the way to New Orleans our bus caught on fire.

"I had gone back to go to bed and all of a sudden I heard this huge noise, which I thought could've been a gunshot. It was the tire blowing on the bus."

Tish - who was with her other daughter Noah Cyrus at the time - recalled how the driver advised her to collect all her belongings and exit the vehicle, before the bus burned to the ground "within three minutes."

She continued: "I panicked, Noah was little, I got her off, my dog, I was trying to get the manager up," Tish said. "He had ear plugs in and was in bed asleep already."

Thankfully, everyone made it out of the vehicle to the side of the road, but Tish struggled to sleep afterwards and though she tried the tranquiliser Ambien, she "hated" it and eventually turned to marijuana on Miley's advice, and she found the drug "really did help" her settle down.

She said: "That's actually how I started smoking. Miley said, 'Mom, why are you putting a chemical in your body that makes you feel so bad the next day?'

"I don't do that in the mornings."

And Tish admitted it is "funny" that, after turning her onto the drug, the 'Wrecking Ball' hitmaker is now "completely sober".

She said: "The funny thing is Miley, she doesn't anymore at all. She's completely sober. She doesn't smoke, nothing."

Meanwhile, Brandi, 33, admitted she was "shocked" by how open her mom was about her habit and is "proud" of her for speaking out.

She said: "So, she's on it and I'm not, which is the funny thing.

"I honestly am shocked about how open she's been about all this.

"Because for us, for the family, we are around her all the time when she is smoking, and she's so great. And we're like, 'The people need to see this. This is too good.' So, I'm just so proud of her for finally owning it, opening up, and being so cool about it."