Sweating and swearing, wielding shovel and trowel, I remove what seems like tons of earth. So why is the rockery not several feet lower than the rest of the garden after all these years? And what is the point of it all when in a month's time the grass will have grown back just as luxuriantly? It is a bit like teaching parts of speech and imagery to third-year pupils: no matter how hard you try to implant the seed of knowledge, no matter how thick the compost with which you surround it, when you seek answers a few weeks later you are faced with the kind of anguished ignorance that Emlyn Hughes portrayed so well on A Question of Sport.
I consider these philosophical points as I toil away, dimly aware of neighbours watching from behind net curtains. I try to fantasise that these are the wives of the locality hoping to catch me ripping off my shirt and downing a bottle of fizz, as in the current television advert.
Even my well developed imagination balks at that one. In truth, they are waiting for what my son calls "Daddy's Bumble Bee Dance". While I pay lip-service to bees, as harmless and ecologically sound members of society, and even illustrate my beliefs with a few bars of Joni Mitchell's "Big Yellow Taxi", the reality is closer to Arthur Askey's "Buzz buzz buzz buzz buzzy bee".
A sudden encounter with a bee in the undergrowth of the rockery leads to me performing, in Clive James's memorable phrase, "like a man in the latter stages of the Hully Gully". I leap backwards, arms flailing, legs kicking, body twitching, while the unfortunate insect buzzes about in a state of panic. My son collapses in helpless mirth while, for all I know, the neighbours charge friends to come and view West Edinburgh's very own Riverdance.
Why is it that, from this spring high point, the state of the garden deteriorates as the summer draws on? My wife will tell you it's because I play cricket every Saturday instead of weeding and pruning. But I can't help but believe there's something more to it. It's that old spring fever, you see, coupled with a teacher's natural inclination to search for deeper explanations and wider ranging illustrations.
My worry is that this madness, like the grass in the rockery, is spreading. Last Saturday, I was about to bite into an Eccles cake. "Daddy, why's that called an Eccles cake?" my son asked. A simple explanation? Not from this teacher, not in the throes of the equinox.
When my wife found us, I had been through the geography bit, explaining Eccles as a suburb of Manchester, had gone multimedia by playing the Hollies song about Jennifer Eccles on the CD player, and was casting about for ways of introducing Eric Cantona's seagulls of philosophy, Lancashire's chances of cricketing success and the fact that Manchester possesses the world's first railway station.
Her long suffering look said it all. For all my efforts at enlightenment, I had missed the most obvious definition: the Eccles I was closest to was the star of the Goon Show. That's all folks!