Enid Bagnold’s play The Chalk Garden can seem difficult, but perhaps that’s intentional, for life is not always easy. While at first it appears that we might be about to watch a drawing room comedy, it mines deeper seams and is often surprisingly frank in what it brings to the surface.

An aged matriarch, her teenage granddaughter, Laurel, and a manservant, live together in a large house on the Sussex Downs, with a chalk garden in which no flowers will grow. The set, as we are accustomed to at Windsor, is beautifully executed and lit, and we open with the arrival of three candidates for the role of Laurel’s governess. A governess is needed due to the absence of Laurel’s mother, Olivia, who left to live with her new husband, whom, Laurel tells us, had been Olivia’s lover while Laurel’s father was still alive. One of the three, Miss Madrigal, reveals herself to be a keen observer and judge of people, and of course she secures the role; it also transpires that she is an expert gardener. (One would imagine that the naming of the old lady’s daughter and granddaughter after plants was deliberate symbolism on the part of the author, something that she appears to deny in the 1958 interview reproduced in the programme.)

Much of what unfolds in Acts 1 and 2, before the interval, are the back stories of Laurel (“I never shake hands, it’s so animal!”), Miss Madrigal (“If I could I would reverse everything”) and Maitland the manservant (“Have you taken your Luminal?”), as they criss-cross the set with the matriarch, Mrs St Maugham, at centre stage. The script delivered a good number of startling lines, candid, revealing, insightful, and often very amusing. Some, however, seemed to be strict “one liners” that didn’t readily connect with what came before nor after. The writing is indeed at times “elliptical”, as the author herself noted.

The play deals with intense issues of trauma, self-control, loss, and the need for love, but this first half struggled to bring much of that to life. This is partly down to the script, which might benefit from some rewriting to improve its clarity and flow, as was done successfully for the 1965 film adaptation. The occasional appearance, for example, of the nurse who is normally upstairs tending to a moribund ex-butler named Pinkbell, whom we never see, seemed little else but a distraction.

Clarity and flow wasn’t helped by some performances on this opening night of the two week run. Unfortunately Siân Phillips (Mrs St Maugham) had a torrid time with her lines, resulting in repeated pauses and much very audible prompting, while I found Edward Fox’s gruff judge occasionally unintelligible. At one point there seemed to be such confusion between the two that a line appeared to be missed out completely by the actors, with only the off-stage prompt delivering it.

Maitland and Madrigal are both characters with traumatic pasts who are rebuilding their lives. John Partridge as Maitland portrayed well the sparky conspiratorial camaraderie he had built with Laurel, but his interaction with Madrigal perhaps remained too muted rather than showing any sign of a developing bond or empathy between them. Jenny Seagrove’s Madrigal maintained a curiously flat delivery throughout; while Madrigal starts out deliberately enigmatic, she is a woman questing for connection, yearning to put her spirit to use, but the gradual revelation of that core of humanity didn’t come across clearly from this performance.

Finty Williams projected some spirit in to the role of Laurel’s mother Olivia, while Elsie Bridgwood showed genuine passion with the madcap Laurel, although the vulnerable Laurel that lies beneath the bravado is perhaps much harder to put across on stage.

With Act 3, after the interval, the script follows a more conventional narrative path, with revelations, connections, tensions and decisions, providing a more satisfyingly dynamic movement towards what is ultimately the play’s quite cheering conclusion.

The Chalk Garden is a far more provocative play that I had anticipated, but I didn’t find the production on this first evening easy to engage with. Certainly parts of the script are difficult, but I think greater emotional intensity and tighter timing are required from the performers to do justice to this rather interesting play.