Welcome to you, Juan1Dia. Did you know that the Brit-speakers usually call zucchinis courgettes? (Thanks, Jo!)
I have to say that our beloved Wordsmith's double entendre was completely lost on me. If I hear just the word marrow (that is), without the word bone in front of it), I think "plant". (An Appalachian corruption of mallow, possibly.)
I gather it has, er, another interpretation.