Tall trees silhouetted against the sky, darkening as the journey into the woods grows deeper, Humperdinck’s fairytale opera Hansel and Gretel (1893) found its ideal setting at Regent’s Park Open Air theatre. In a collaboration with English National Opera, the theatre’s artistic director, Timothy Sheader, has created a bewitching show full of charm, surprise and enough ribald wit to keep the lid on schmaltz. Adults singing children’s roles can push up the squirm factor to an uncomfortable level. Not here.

The bustling presence of children and students from ArtsEd, Pimlico Musical Foundation and Bird College conservatoire ensured a youthful and engaging atmosphere. Above all, the mezzo-soprano Rachel Kelly and soprano Susanna Hurrell, singing the title roles of the children lost in the forest, were unbeatable: credible, touching, and terrific actors and singers who know when to stop. Both have burgeoning careers at the Royal Opera House and elsewhere. They were transformed beyond recognition here, lanky, ageless children in denim dungarees and check shirts.

Conducted with flair and impetus by Ben Glassberg, members of the ENO orchestra, hidden behind a screen, played a reduction of the score by Derek J Clark, which turned all into admirable soloists. The loss of Humperdinck’s heavy, Wagner-inspired textures if anything liberated the piece, suiting the open-air context and leavening some of the work’s weightier psychological implications. So this production, in David Pountney’s familiar and robust translation, is unburdened by undertone: no message about the planet, or poverty, or child molesters, or the risks of E numbers in houses made of luridly coloured iced biscuits. Were you buying it, this Hansel and Gretel would be in the “free from” aisle.

Duncan Rock as the ribald, drunken father, and Rosie Aldridge as the tight-lipped, oppressed mother, have stylish stage presence. Gillian Keith’s Sandman and He Wu’s Dew Fairy contribute memorable cameos, all helped by Peter McKintosh’s beautiful designs. The witch herself, played by Alasdair Elliott in vulgar drag, red kitten heels and polka dot slit dress, is straightforwardly mean and nasty. Among many skilful touches, Sheader and movement director Lizzi Gee turned the 14 angels who protect the sleeping children into shiny, blond-wigged, white-uniformed flight attendants (that whole dream sequence worked triumphantly); trees are made of upturned broomsticks; gingerbread children’s eyes glow green; the family’s wooden house is transformed before our eyes into part of the forest, then turns into the witch’s house: enough magic, but enough sap and vigour too. You can catch Hansel and Gretel elsewhere this season, with Susan Bullock playing both mother and witch at the Theatre in the Woods at Grange Park Opera.

This is the bicentenary of Jacques Offenbach (1819-80), though you may not have realised. German-born, French by adoption, the composer best known for the lyricism of Les Contes d’Hoffmann or the slapstick of Orphée aux enfers doesn’t sit quite comfortably in the British operatic landscape. The humour in his operettas lacks the steely edge of Gilbert and Sullivan, or perhaps their essential French charm is lost in often effortful translation. Garsington Opera has form with his rarities. After Vert-Vert in 2014, this year they have staged the UK premiere of Fantasio (1872), a late flop about a court jester, not short of rapturous music and exuberant choruses but whichever way you read it, a thin tale.

At first sight it didn’t look promising: Toulouse-Lautrec and De Chirico meet the Munchkins. Yet there’s a tender melancholy to the music (appreciated, too, by Mark Elder, who conducted it in a concert performance in 2013 and a recording for Opera Rara), and several showpiece numbers, which Garsington’s cast and orchestra, conducted by Justin Doyle, performed impressively. Jennifer France was outstanding as Princess Elsbeth. Her sparkling coloratura arias were a reminder of how versatile this rising-star soprano is (recently seen as Ophelia in Brett Dean’s Hamlet, and as Ice in Stuart MacRae’s Anthropocene). Hanna Hipp, too, played the title role with panache.

She, France and the rest of the soloists, notable among them Huw Montague Rendall as the Prince, did their best to deliver the screeds of spoken dialogue, cleverly translated by Jeremy Sams. Even his skills couldn’t disguise the weakness of the original material. The chorus sang excellently, and their routines were well rehearsed and nimble. Directed by Martin Duncan and designed by Francis O’Connor, Fantasio is a once-in-a-lifetime piece. That’s to say, you won’t want to see it twice. Let’s be grateful, though, that places such as Garsington exist to give us the chance. For Offenbach favourites, ENO has a new Orpheus in the World directed by Emma Rice in the autumn, and Blackheath Halls Opera is staging La belle Hélène next month. Can-cans all the way.

The tenor Mark Padmore, a resident artist at this year’s Aldeburgh festival, joined forces with the baritone Roderick Williams, pianist Julius Drake and, as narrator, the actor Rory Kinnear for a programme at a sold-out Snape Maltings entitled The Sea, The Sea. If only all concerts had this elegance and variety of construction. Far-ranging, including songs by Haydn, Fauré and Schubert as well as Stanford, Britten and Tippett, it scotched any narrow idea of an island race and embraced wider horizons. As an encore all four performers, Drake and Kinnear too, sang – winningly – an arrangement by Roderick Williams of Shenandoah: a river, not a sea but I expect it gets there eventually.

Star ratings (out of five)
Hansel and Gretel ★★★★
Fantasio ★★★
The Sea, The Sea ★★★★★

• Fantasio is in rep at Garsington Opera until 20 July