You see, "gardener's" is what strikes me. The rest is about strength, that's what oaks are. They last, and they grow. But a gardener helps that, he doesn't hinder it. It's almost as if you're attributing need. There's a conflict there between hurt and dependence.
It's like the song from 'My Fair Lady'.
"Just like a habit one can always break.
I've grown accustomed to her."
One could even bring it across more by changing 'gardener' to 'tender', as in the noun of one who tends. Of course, you'd have the pun as well.
Strong stuff though. Chin up, it takes a whole lot to fell a mighty oak tree.