Since this word is made up of a single kanji, it should use the kun'yomi reading. When learning the kanji, you didn't learn that reading, so here's a mnemonic to help you with this word:
This is a magic root that turns you into a horse. You take a bite and let out a loud neigh (ね)!
You can eat the roots of this flower.
It seems that this problem has really deep roots.
You might think he’s a great person but he’s really a horrible man at heart.