Mr. Bell's secret fertilizer

Those of you with children may be familiar with the songs of Raffi. I like Raffi. I may be a bit tired of him after listening to him for almost 6 years, but he remains a decent fellow in my opinion. Some of his songs are downright fun like "Bananaphone;" others, more serious, convey his respect for nature. Some are full of lessons and meaning and others are empty but entertaining. Yet all of them are acceptable for listening. There remains one song, though, that I can't figure out. "The Changing Garden of Mr. Bell" is a haunting little number about a man who has a colorful and everchanging garden in his yard. Seems innocent enough, right? And it could be until our attention is called to a photo on Mr. Bell's mantle that pictures what may be his missing wife and child:

I once saw a photograph, upon his mantle shelf
Of a beautiful lady, a child in her arms
And the young Mr. Bell himself
I wondered out loud about them, and he answered
In the strangest way,
He just said "look, see how the garden grows,
It's always changing ev‘ry day"

from The Changing Garden Of Mr. Bell
(Janice Hubbard/Michael Silversher)

Do you get the feeling that Mr. Bell might have some skeletons in his garden? You might think that I'm reaching but for the closing lines of the song:

Life's a mystery, full of secrets that might tell
In the changing garden of Mister Bell

Convinced now? It gets even weirder:

See the sun through the curtain lace
Dapple his face and hands

What man in his right mind has lace curtains? Clearly there's something very wrong with Mr. Bell. And I'm left wondering what a song about a man who possibly murdered and buried his wife and kid in his garden is doing on a children's album. What was Raffi thinking?