A fine-looking head of lettuce was the catalyst for considerable change in the life of actor Ruth McCabe. A few years ago "one of the kids got some lettuce up in the local shop, and of course picked the greenest one," she recounts. "I washed it, and put it in the salad bowl. I took one mouthful and I said, `I don't think we should eat this.'"
It tasted all wrong. Later, she heard about a crop in north county Dublin that had been mistakenly treated with too much pesticide by an apprentice. "The lettuce was poisoned," she says with horror. "It was very frightening. Imagine - the idea of poisoning your family at the dinner table!"
The obvious way of preventing this grisly prospect was simply to grow as much organic food as possible. And, as there was not enough room in the family garden, an allotment was the answer. "So, it was a matter of putting my name down with Fingal County Council - God bless them - and getting onto a waiting list."
The waiting was painful, as Ruth was hungry for action. But on a January day, three growing seasons ago, her tenth-of-an-acre plot was finally handed over.
"You pay them £18 a year. It's their allotment, and you're a tenant. In terms of old-fashioned socialism, it's about as decent as you can get. And you have fab neighbours, which was the thing I was excited about - having older, more experienced gardening neighbours.
"But," she adds, "when you're out here, you don't have the time to gawk at other people's methods."
"Out here" is not far from Donabate, where a large field is portioned into dozens of allotments, most with their own shed. Some sheds are of the ready-made wooden variety, others are cobbled together from cast-off timber and iron, and one - the envy of all - is a prefabricated cabin that was once a security hut, and still bears the command: "Visitors must report to Reception". The building that sits on Ruth and her husband Colman's territory is a green, corrugated affair: "I know it's just a shed, but it's a palace to us."
A fresh breeze blows off the Rogerstown estuary, carrying with it the ragged-winged, randomly wheeling rooks. The only sounds are their raucous cries, and the hum and clank of nearby farm machinery. It is absolute peace: time is irrelevant.
Or rather, it may seem irrelevant, but in fact, time is the thing that all allotment holders are in constant need of - especially here, where the heavy north Dublin clay eats chunks of it. Buckets of time is required for the business of larding the weighty soil with barrows of manure and compost, if it is to yield worthwhile produce. And more buckets of time - and mulching and digging - are needed to keep the soil's surface from sealing into a hard, brick-like pan that strangles all vegetation: except, of course, the ever-present choking weeds, prime enemy of the allotment-holder.
When she first mapped out her plans for the patch, Ruth intended it to be "low-labour, and for my not being very strong" - which meant raised beds and a no-dig regime. The latter proved to be "a nonsense: I don't think that you can garden without digging, not on this soil". And luckily, Colman, whose interest was an unknown quantity at first, turned out to be "devoted to the allotment. He digs. And because he grew up on a farm, he knows things about growing that he doesn't know he knows!"
Crops that "sit in the soil and look after themselves" were imperative, such as onions ("we're not going to have to buy any for the second year in a row: the shed at home is full"), beetroot, brassicas, artichokes, rhubarb, leeks (grown lovingly from seed by Colman) and - Ruth's pride and joy - a wonderful stand of `Autumn Bliss' raspberries. "They're a very good choice for busy people. They don't need staking, and in late January or early February you prune the whole lot to about six inches from the ground."
The narrow tract is enclosed with green, wind-proof mesh (which also helps to deter carrot-fly) and a delightfully wobbly brick path meanders down the centre. Nasturtiums scramble through the food-crops, attracting pollinating insects and adding a happy splash of colour. Understandably, this alluring place is "the centre of our lives at the moment. We don't expect the kids to come out and slave on it, but we're hoping that when they approach their middle age they'll get this fever.
"And," she adds with some fervour, "I hope that there will still be a situation in this country where they can get an allotment. Because they probably won't be able to afford a house. Allotments for all! That's my war-cry."