I use word roots to learn new English words.
I am also using roots as I learn Spanish, when the root is similar to a related English word.
I find that using roots slows me down a little, because I have to remember two things. I first have to remember the root, and then I have to remember how the root changes to become the word I'm trying to remember.
But it does help me remember; it's better than not remembering at all.
Ultimately, I want to remember automatically, without using roots. That just comes with practice and repetition, and by reading, listening, and talking.