Actor Matthew McConaughey only cuts his hair when it’s a full moon – in order to preserve his luscious locks.

The “Magic Mike” hunk started losing his hair in the late 1990s and began Regenix on his scalp to stave off baldness.

McConaughey still uses the product to this day and he swears by its ability to keep his mane in tip-top shape, telling Elle magazine, “Back in 1999, my hair was fallin’ out, so I started (using) this stuff. And, son of a gun, if I didn’t bring my hair back so well that people thought that I went and got plugs. … I believe that I’m proving the product.”

In addition, the 43-year-old studies the lunar calendar to determine when it’s the best time to get a trim.

He says, “If you want your hair to be thicker, cut it when the moon is about to be full – a heavy, full, waxing moon. Do not cut it when the moon’s waning.

“Why do you think that (farmers) plant at certain times of the year? It’s not hippie-dippie stuff. Look, how do they know when you reap, when you sow, when you plant?”