In the years that I have been going to Glyndebourne, I have become middle-aged. On my first visit, in 1995, I was young, arriving late from London in a hired sports car, running from the car park to find my splendidly bemedalled father looking reproachfully at his watch.

Now I do things differently, arriving with plenty of time to spare and my husband driving. We sit in the tea room with strawberries and cream, we wander round the herbaceous borders sipping champagne, we investigate the shop selling Glyndebourne scarves and umbrellas, and still the performance is some way off, pleasurably anticipated. There is no rush.

Unless you are a tourist (and there are very few of those), Glyndebourne is not something you do just once. It is an annual event around which family, work, conferences, holidays and the other demands that fill up our summers have to be fitted. It requires long-term planning, creative thinking, moments of courageous decision-making, a careful marshalling of resources, financial and temporal, logistical skill and administrative efficiency. A career in academic management is not a bad preparation.

Music reviewers can do far better justice to the performances than I can; suffice to say that the opera at Glyndebourne is world-class, with outstanding singers, many of them up-and-coming, and technically superb productions full of inventive detail. What intrigues me is the annual cycle of organisation required to end up on a particular evening at an opera house out in the English countryside where magic happens. The sense of achievement that the performers must feel is as nothing compared to my own satisfaction at having pulled it off one more time.

ÖйúAƬ

The history of Glyndebourne as an opera house began in 1934 when John Christie, who had inherited the property from his grandfather, held the first opera festival in the purpose-built auditorium. Christie's wife, Audrey Mildmay, was a professional opera singer with the right contacts, and the first six-week season featured small-scale productions of Mozart's Le nozze di Figaro and Cos¨¬ fan tutte, works that have continued to feature on the Glyndebourne programme ever since.

The present opera house at Glyndebourne, built between 1992 and 1994, increased the seating capacity from 850 to 1,200 as well as providing modern backstage areas and rehearsal spaces. Old-timers like my father remember the "old" opera theatre with affection but are delighted with the new one, and indeed it is a beautiful space with brilliant acoustics. Even high up in the upper circle, the top level of four, you can hear every word (and note).

ÖйúAƬ

Each generation of Glyndebourne-goers remembers a slightly different experience. While my father remembers the original Glyndebourne theatre, I remember the pre-digital days when everything was done by mail or telephone. The Glyndebourne year began in autumn, with the arrival of a small brochure announcing the line-up for next year's season, which always runs from May to August. This was the signal to start brushing up on the operas that were to be featured and, having no idea which one we would finally get tickets for, we had to prepare for every eventuality. CDs of each opera invariably featured as Christmas presents, and my husband, being genuinely musical, would reminisce about various productions he had heard or seen in the past.

Since the main preoccupation of most Glyndebourne-goers is how to secure a ticket in the teeth of ferocious competition, as January went by we had to be on the alert. The company operates a strictly hierarchical system of ticket distribution. At the very top of the hierarchy are the "Members", the august body of donors who get first choice of the tickets. The new opera house was funded almost entirely by donations from loyal opera fans like my father, who thus secured, for the rest of their lives, first call on more than a quarter of the seats each season.

Then there are the "Associate Members", who pay a hefty joining fee plus an annual subscription, in exchange for second place in the ticket lottery. As members of the mailing list, at a modest ?10 per year, we wait our turn several rungs down the ladder - though not quite languishing at the very bottom with the "General Public".

Early in the new year we would be given the date at which bookings for the likes of us would open, a date usually in March or April. On that date, and not before, we could post in a booking form, or telephone the box office, giving as many dates as possible, after which we would be informed of the one date when seats were available at a price we could afford without a second mortgage.

Now, it is all done via the Glyndebourne website and, I must admit, I have mixed feelings. It is undoubtedly a more convenient way to find out about the operas, when they are on and who is singing and directing and so on, but, as with so many "choices", what we are offered is merely an illusion of choice.

Because of the preferential booking system, some of the operas are entirely sold out before we can begin to book our tickets; almost all the cheapest seats for most of the performances have also gone (I imagine many of the Members fall into the category of impoverished gentry). At two minutes past midnight on the day we are allowed to start booking, we are left scrambling for the last few tickets at something approximating a price we can afford. We have very little choice about which opera we see, or when - we take what we can get. It is no coincidence that the only year I failed to get tickets for Glyndebourne was last year, the first year that online booking was introduced.

ÖйúAƬ

Once the trauma of the ticket-buying is past, other factors come into play. The first imperative is to book some accommodation and here again, there is no time to lose. The nearest town to Glyndebourne is Lewes, a beautiful little market town that is arguably the model for Ruth Rendell's Kingsmarkham in her series of Inspector Wexford detective novels. Immediate recourse to the telephone and/or website is essential once the date is in the diary, so it is not unusual for my friendly bed-and-breakfast hosts to know about our Glyndebourne visit before my husband does. One year (2005, La Cenerentola), we experimented with catching the train down from London, along with a jolly crowd of dinner-jacketed colleagues but, although the Glyndebourne operation is generous with its shuttles to and from the station, it made for a long night - and hard on the feet of the stiletto-wearers.

This points to the next challenge: what to wear. It's easy for men, of course - they can wheel out their dinner suits and the only decision to make is the waistcoat or the cummerbund. For women, it's the usual minefield. Elaborate formal numbers of the kind seen on the red carpet at the Oscars are far too dressy; on the other hand, a floaty summer dress looks a little casual on the arm of a dinner jacket. Something approaching a cocktail frock, not too long and certainly not too short, is about the right register.

ÖйúAƬ

On one never-to-be-forgotten occasion (1996, Theodora) I bought an outfit in a hurry from a high-street store, a rather striking affair in pink and white stripes. During the pre-performance stroll on the lawn I saw, coming towards me and completely inescapable, a woman wearing the identical ensemble. We were drawn inexorably towards each other in the full glare of dozens of opera-goers and I'm sure she was as mortified as I was, although she at least had the satisfaction of knowing that her dress was a good two sizes smaller than mine. Since that experience I have made a practice of buying Glyndebourne dresses well offshore.

The other big decision is culinary. The operas start early in order to accommodate a long dinner break of about an hour and a half. Many people associate Glyndebourne with picnics, and this is indeed the first choice of a large number of intrepid traditionalists, who bring with them the full panoply of middle-class picnic bric-¨¤-brac, including folding tables, chairs, rugs, hampers, good-quality plastic plates and enough food for a marching army. Among my favourite sights at Glyndebourne are the fully laden picnic tables set up like a Fulham dinner party, complete with white tablecloth and napkins, matching crockery and crystal, and silver candelabra with tall white candles punctuating the twilight.

We did try it, once, on a more modest scale, sitting on car rugs with plastic glasses and smoked salmon, but ended up shivering beneath the rugs as a light rain fell (2003, Die Fledermaus). Finances permitting, our preference is for the self-service buffet in the elegantly-named Nether Wallop, the least expensive of the three dining rooms set up in converted barns around the estate. There is something delightful about formal dining amidst candlelight and bright conversation, with the first part of the opera to marvel over while the second part is still a tempting promise.

When the performance finishes, there is still time to linger for a last glass of champagne at the outdoor bar under a sail roof as the summer light fades. It is the kind of evening you want never to end. This is the moment for a last ritual, the ceremonial purchase of the annual Glyndebourne mug. Not noted as a collector - my husband and children will testify to my zeal for decluttering - I nevertheless enjoy my growing collection of Glyndebourne mugs which I use daily, some at work and some at home. I like the one with gold lettering celebrating the 75th anniversary (2009, L'elisir d'amore), the one that is decorated with a 1950s-style painting of modern opera-goers in the flower gardens outside the house (2002, Don Giovanni), and the one that has the silhouette of Mozart appearing as a splotch on a Friesian cow (2000, Cos¨¬ fan tutte).

I know, I know, it's all reprehensibly middle class - but that is high culture for you. In a pop-politics kind of way, Glyndebourne exemplifies the performance of social class, from the "stately home" location to the hierarchical ticket system and the well-bred voices on the lawns. Compensating for this is an almost total lack of glamour or celebrity. In all my years of going to Glyndebourne, I have never seen anyone famous, whether politician, television presenter or film star, though the soloists themselves, the true stars, often come out to mingle at the bar after the performance.

I am well aware that in admitting my loyalty to Glyndebourne I have marked myself as not just middle-aged but irretrievably middle class. I remain unrepentant. Glyndebourne is the English bourgeoisie at its best, unselfconscious, authentic and (more or less) uncommodified.

ÖйúAƬ