Back when I reviewed The Secret Garden - this seems like a lifetime ago - I promised follow-up remarks, which mostly consist of commentary on where the libretto went wrong.
Here's what I said in the my published review:
Harrison’s libretto hews closely to the story line of the original, though some of the changes are unnecessary and perhaps damaging to the effectiveness of the opera, by shifting some weight from the children to the adults. The invalid Colin Craven’s distant father Archibald is somewhat more present in the opera than the novel. Colin’s moral recovery and increasing physical strength don’t happen gradually over the course of the opera, but are instead timed with his father’s return from traveling, perhaps the most serious issue.
The entire Sowerby family, originally poor Yorkshire cottagers, seems to have gotten an economic upgrade, softening the stark class differences that are so obvious in Burnett. And the gruff gardener Ben Weatherstaff, whose greatest significance is his connection to Colin’s dead mother and her garden, here becomes the opera’s comic relief.
The most problematic issue with the libretto, however, is that it is cast almost entirely as conversation, with just one short aria, one brief duet, and a single ensemble, all falling late in the opera.Well, that's the least of it. A playwright friend of mine and I exchanged email a couple of weeks after the primo, and I listed a few more issues, divergences of emphasis that overall softened the message of the book and resulted in a much blunter opera than it could have been. Owing to space and time constraints, I really couldn't rip the libretto to the extent that it deserves. And here we go with the rest of the problems.
In the book, Mary is a sullen, bossy, and sour child. Physically, she is sallow, has limp hair, and is borderline ugly. Little of this came across in the music, direction, or her costuming and makeup, and it's crucial to her transformation to adequately present how she starts. Really, she is an extraordinarily unappealing child. And I hated the opening, with Mary bouncing around and being obnoxious. In the book, it is apparent that one reason she is so unattractive is that she is enervated. She has no energy; it is sapped by the heat of the Indian sun.
Parallel to this, you don't get quite enough sense of what a pill Colin is. You never see him throw one of his spectacular temper tantrums.
Mary, Colin, and Dickon don't spend nearly enough time in the garden, and as a result, you get no sense of Mary and Colin's gradual transformation from near-invalid to healthy, bright-eyed English children. Making Colin's transformation a sudden thing at the end, so that it happens in front of his father, undercuts the Power of Nature theme that is central to the book. So does the elimination of the doctor, who represents man-made medicine. Medicine and the slightly evil doctor fail to cure Colin, but Nature does; if this sounds like Christian Science propaganda to you, why, that's exactly what it is. Frances Hodgson Burnett dabbled in Christian Science and Theosophy, she lost a beloved child at a young age, and this book is surely part of how she worked out her grief at her son's death.
I mentioned that the Sowerby family is middle class, more or less, in the opera. Dickon wears tweeds - so appropriate for a country boy! But in the book, they are dirt-poor, with a dozen children, mother baking bread daily to keep everyone fed, and very little money. Dickon is the poor-kid equivalent of a "magic Negro," if you know the term: he can befriend any animal, communicate with it, tame it, make gardens grow from nothing. He is the leader of the healing-through-nature effort; he knows, without book learning, that nature is better than medicine. Making him and his family middle class also takes away some of the pathos of the book, as when Martha Sowerby brings fresh bread (or is it milk?) to the invalids and we, the readers, know perfectly well that her family just can't afford this - and of course the rich Craven family can afford anything.
One last point: Jeff Dunn report to me that the children sitting near him were extremely attentive, and he asked them how they liked the opera. They all liked it. My playwright friend reports the opposite: kids near her were restless and told her they didn't like it at all. So, the opinion of the youth is divided.