Children, it seems, barely arrive in this world before they begin longing for a new one, especially if it contains magic. Such yearnings seem easy to fulfil, but are in fact the hardest to get right. You can have all the traditional elements of fantasy and still, like Isabel Hoving’s The Dream Merchant (Walker, £14.99), get it wrong thanks to leaden characterisation and plotting, or, as with Giant Surprise, the atrocious new picture-book rip-off of C. S. Lewis’s Narnia, fail even to respect somebody else’s original.

Jane Johnson’s The Secret Country gets it absolutely right. The editor in charge of the Tolkien estate gives us a few familiar features in her tale of a young boy who discovers his gravely ill mother is the Queen of Eidolon, a magical world swarming with dragons, elves and goblins. Ben goes into a pet shop to buy Mongolian fighting fish with his pocket money, but is stopped by a determined talking cat which tells him that Eidolon is in danger. One of the chief crooks importing its fauna to our world is none other than Ben’s Awful Uncle Aleister, bent on providing direwolfs, sabre-toothed tigers and camelopards to human hunters frustrated by mere foxes. Before long Ben and his new friends are dodging the evil Dodman and a host of goblins and enjoying an adventure perfect for readers of 7+. There are children like mine who will read any book with a dragon on the cover, but this one stands out thanks to its charming and humorous mixture of the mundane and the magical.

Mary Hoffman’s Stravaganza trilogy reaches its conclusion in City of Flowers, to which the hero, Sky “stravagates” after smelling a mysterious bottle of scent. Each of the novels is set in a city state of Talia, and Sky arrives in a version of Renaissance Florence, Giglia, where a political battle as vicious as that between the Medicis and the Sforzas is going on. The di Chimici are master-perfumers, but their plans for a wedding are upset by an attempt to poison the head of the family. Sky and his fellow-Stravagantes here and in Talia join forces. Although the first in the series worried me in offering a seriously sick child life and health in another world, the consistently interesting and versatile Hoffman has caught up all the threads from her first two books to weave a baroque thriller about art, murder, love and family, and does not descend into escapism. Gorgeously produced with marbled endpapers, illustrations by Peter Bailey and a sumptuous cover, these books are a joy to hold as well as to read.

Matt Thorne’s 39 Castles series is set in a future England, divided into castle communities living in semi-feudal ferment. In Kingmaker’s Castle, Eleanor, chosen to join the secret organisation, must rescue her friend Mary, kidnapped by Anderson to be the Queen of all England. Can Anderson be trusted, or will swords and staffs have to knock some sense into a castle run entirely by children? The action is fast and writing terse, but Thorne’s world needs more detail: I couldn’t help wondering how this community managed to get hold of orange juice.

Angie Sage’s Magyk combines the usual ingredients (plus a delightful boat which turns into a dragon) of good and bad magic, lost children, dangerous quests and monster-infested marshes with a dollop of robust lavatorial humour. Within two pages, I heaved a sigh of relief, knowing it would keep my nine-year-old quiet as he followed the adventures of the princess smuggled out of her murdered mother’s room and adopted by Septimus Heap and family. Warm, funny and humane, Sage takes care with the destiny of even her smallest characters, and is a real discovery.

The real star of this month’s fantasies is Cat Weatherill’s Barkbelly, creator of a world in which giant hedgehogs pull ploughs and the hero, a wooden boy, hatches out of an egg. Like Pinocchio, Barkbelly finds his hard flesh a mixed blessing when he kills a small schoolmate. On his journey to discovering his real mother he also discovers wisdom, which comes at heartbreaking price. What makes the book special is not just the quality of the author’s imagination but her richly poetic style. Weatherill, has written the kind of classic tale that may have more resonance for adults than it does for children.

The Secret Country (7+) by Jane Johnson (Simon & Schuster, £12.99; offer £10.39, call 0870 1608080); City of Flowers (10+) by Mary Hoffman (Bloomsbury, £12.99; offer £10.39); Kingmaker’s Castle (11+) by Matt Thorne (Faber, £4.99; offer £4.24); Magyk (9+) by Angie Sage (Bloomsbury, £12.99; offer £10.39); Barkbelly (10+) by Cat Weatherill (Puffin, £9.99; offer £8.49)

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