There are few things sadder than a magic trick that doesn’t come off, and this live-action Disney movie feels like the cinematic equivalent of one. It desperately wants to be a poetically enchanting fable about the joys and problems of parenthood, but instead emerges as a heavy-handedly prosaic shaggy-dog story. Actually it’s more of a shaggy-bush tale, being about a little boy who literally grows out of the ground like a tree or a cornstalk. It’s quite just, therefore, to observe that the adjectives one’s most apt to use in describing it are sappy and corny.

The whole odd narrative is told in flashback by Cindy and Jim Green (Jennifer Garner and Joel Edgerton), as they try to convince an adoption-agency interviewer (Shohreh Aghdashloo) to approve their application. When their persistent effort to have a child had failed, they tearfully spent an evening imagining their long-desired offspring’s qualities, writing them down on little slips of paper that they placed in a small wooden box they then buried in their vegetable garden. As the slept a magical storm came up—washing down their house, though not breaking the drought in the surrounding country—and little Timothy (CJ Adams) showed up all muddy, with green leaves growing on his ankles. Knowing an answered prayer when they see one, they decided to unofficially adopt the strange, almost preternaturally docile boy as their own.

Over the course of his time with the Greens—a span that diminishes as the leaves on his legs die off, though he keeps that a secret—they learn about how to raise a child mostly through two major episodes. One has to do with Timothy’s friendship with an outcast girl named Joni (Odeya Rush) which Cindy considers dangerous and initially tries to obstruct. The other has Jim insisting that the awkward boy go out for his company’s soccer team despite the misgivings of the coach (Common)—largely so that he can show his own father (David Morse), a tough, macho guy he feels ignored him, how a real dad should behave. The counterpart is Cindy’s desire to exaggerate Timothy’s talents in the face of her obnoxious sister’s (Rosemarie Dewitt) overachieving kids.

There’s more. The picturesque town where the Greens live is dominated by the Crudstaff family, owners of the pencil factory that’s the mainstay of its economy. Jim works on the assembly line there, and has to put up with arrogant boss Franklin (Ron Livingston), who’s threatening layoffs or complete closure. Cindy works at the town museum under the stern eye of Franklin’s mother, town matriarch Bernice (Dianne Wiest). Timothy becomes involved with both his temporary parents’ jobs, not always with the happiest of results. He also shows a precocious degree of empathy in dealing with the death of Cindy’s Uncle Bub (M. Emmet Walsh), who raised her along with his loving wife (Lois Smith).

This is a strong cast for such a fragile bit of whimsical uplift, but not all of them are at their best. Adams’s stiffness suits the fey young boy, while Morse and (surprisingly) Common are excellent; and it’s a pleasure to see Walsh again, as frail as he seems, ably abetted by Smith. Rush is fine as well. But DeWitt, Livingston and Wiest come on too strong (though the latter has one nice scene when Timothy sketches her). Unfortunately, Garner is all over the place as Cindy, never settling down and coming across as a gabbling ninny. Edgerton, though calmer, seems equally ill-at-ease. Their connecting scenes with Aghdashloo are especially painful, but they aren’t much better elsewhere. In general director Peter Hedges should have wielded a firmer hand.

“Timothy Green” is visually attractive, with cinematographer John Toll making good use of the locations and Wynn Thomas’ production design. But Andrew Mondshein’s editing could be crisper, and Geoff Zanelli’s score opts for the most banal effect. They help insure that while the movie is good to look at, it winds up as a sluggish fairy-tale, more silly than magical from beginning to end. When Timothy stumbles all over the field when trying out for the soccer team, he blissfully tells the coach, “I can only get better.” Unfortunately, the movie proves that’s not always the case: it remains a non-starter throughout.