When New York’s performing arts season — from September to June — came to a close, my parents would arrange outings to outdoor musical events, especially at Tanglewood and Robin Hood Dell in Philadelphia. The excursion, the picnic, and the starry skies enhanced my childhood memories of those individual performances on warm nights. The enchantment endured when I later discovered, during my student travels abroad, an abundance of theatrical and music festivals in bucolic settings, some centuries-old, like entertainments at such aristocratic venues as Versailles.

Most frequently, though, I return to English country house opera, a genre of summer performance art that combines the intimacy of being treated like a familiar houseguest with the liberty of wandering about the host’s burgeoning gardens in waning sunlight. A main feature is the roughly 90-minute intermission during which the audience dines either picnic-style in the gardens or in well-appointed dining rooms. On a recent weekend, I attended operas at two different country houses: Benjamin Britten’s “Albert Herring” at the long-established Glyndebourne Festival in East Sussex and Verdi’s “Falstaff” at Nevill Holt in Leicestershire, a newer version of this hospitable form.

The example was first set at Glyndebourne about 75 years ago. Following his marriage to the singer Audrey Mildmay, and a honeymoon abroad attending the Salzburg and Bayreuth festivals, the estate’s owner, John Christie, was inspired to build an opera house seating an audience of 300, expanding upon the Organ Room he had previously built for amateur opera performances. Rudolf Bing was an early general manager, and the artistic quality was guaranteed by a pair of German émigrés, Fritz Busch and Carl Ebert, a conductor and theater manager, respectively, who, forced to leave Nazi Germany, never dreamed they would make successful careers in the English countryside.

In 1994, Glyndebourne opened with a new opera house commissioned by John’s son, Sir George Christie. Designed by Michael Hopkins and Partners, the round brick structure with multilevel outdoor terraces seats 1,200; its horseshoe-shaped, domed auditorium is paneled in softly lit old pitch pine that retains the warmth of the original building. And the balconies are faced with simple V-shaped metal reflectors that with single light bulbs radiate the glitter one associates with opera houses.

Evening clothes are de rigueur for these occasions in the country-house custom of dressing for dinner. Like others in this handsome crowd, I arrived long before the 5:45 p.m. curtain to get the best of the late afternoon light in the garden, with its walled enclosures and series of herbaceous borders at the height of summer bloom (vocalizing can be heard in the distance). As always, there is a scramble as parties stake out their dining spots with blankets or folding tables and chairs in corners of the garden or on the great lawns separated from grazing sheep by an almost invisible ditch called a ha-ha. My spot was a bench by the pond, banked with white daisies and with bleating sheep behind.

The performance. “Albert Herring” made its premiere at Glyndebourne in 1947; the current production, in revival, originated in 1985, directed by Peter Hall. A British audience does not miss a single nuance of this story — both the humor and the pathos — about a Suffolk market town that selects a young grocer boy to be the May King when no local girl is considered virtuous enough by the town leaders. When the curtain rises on Lady Billows’s drawing room, where the committee is meeting, the tongue-in-cheek set is not unlike Glyndebourne’s own Organ Room, with its high-bowed, small-paned windows overlooking the garden.

Britten’s opera captures the confining mores of small-town life and the anxiety of its inhibited hero. Egged on to drink lemonade spiked with rum by his young friends following his coronation (a musical moment echoing “Tristan,” according to a program note), he sets out on a night of debauchery in a neighboring town, thus establishing his independence. In this production, the 1985 Albert Herring was now performing the role of the Mayor. The ensemble singing and children’s voices that characterize so many of Britten’s works were particularly fine. And the sets, the grocery store interior on the main street and the tented fête in the churchyard, conjured up perfectly the 1890s Britten intended.

Equally loved by the British, Verdi’s “Falstaff” was given a rousing performance the next night in the 18th-century stable block of Nevill Holt, a country house that dates back to the 15th century. A northern offshoot of the Grange Park Opera in Hampshire, founded in 1998 by the conductor and opera impresario Wasfi Kani, it has many of the Grange’s picturesque amenities, such as the blue-and-white marquees from Jodhpur for outdoor dining. In both locations Ms. Kani has achieved what she calls a balance between an improvised house party and quality opera.

Once the home of the Cunard shipping family, Nevill Holt was purchased in 2000 by David Ross, the co-founder of Carphone Warehouse, Europe’s largest mobile phone retailer, who had become a patron of the Grange. When he heard that Ms. Kani was hoping to expand at an estate in his area, the story goes, he sent her an e-mail saying: “If you don’t use mine, I will never speak to you again.” This summer was its sixth season, featuring the Grange’s young singers called Rising Stars.

During the pre-opera garden walk, the head gardener, Jane Rogers, who has overseen a restoration of the grounds, was on hand to guide visitors and identify plants for curious gardeners. The south lawn, with its wide borders in a primarily magenta and lavender palette, leads to an Italian walled garden, with a symmetrical grove of ilex and overhanging fig trees. A door in the wall opens into the extensive kitchen garden with pathways under both willow and currant arches, and on the walls espaliered peaches and nectarines. All this and opera, too.

As the bell rang, the audience walked around to the front of the house, with its crenellated parapet and balustraded green lawn passing by the estate’s own church, to file into the imposing quasi-medieval stable block. The theater, seamless with the structure, has been built within the stable yard, with the dressing rooms the stables themselves.

“Falstaff” is based on Shakespeare’s “The Merry Wives of Windsor,” and never were the wives merrier than in this exuberant production, in which the two women in question dealt with identical love letters they received from the title character. Though the restricted stage required a shallow set, the designers achieved visual distance both with vertical levels and views of a silhouetted St. Paul’s through the window of the Garter Inn, Falstaff’s hangout, and also from Alice Ford’s Windsor apartment, overlooking the Thames — into which Falstaff is eventually tumbled.

In modern-day dress, the costumes were clearly chic without being over-stylish, thus adding to the dailiness of the shenanigans. At one point, to emphasize the contemporariness of the plot, the distinctive silhouette of Norman Foster’s Swiss Re headquarters, dubbed the “Gherkin,” appeared on the skyline next to St. Paul’s. With the split-second timing and hilarity of a farce, the singers never missed a beat of the score or of the dramatic action, giving Falstaff his comeuppance, finally, in the mysterious depths of Windsor Great Park.

Upon leaving, there was still a glimmer of daylight as one looked out over the Welland Valley onto an Arcadian landscape that appears as classic as the setting of Nevill Holt itself. I shall retain that view as the season for opera begins again in New York, and I wend my way through the hustle and bustle of taxis at the performance end.

The Glyndebourne Festival season continues through August 31. While performances are usually sold-out, an e-mail alert offers information on returns and availability. For more information, please go to glyndebourne.com.

“Falstaff” will be reprised at Grange Park Opera on September 20 and September 21, and at London’s Cadogan Hall, near Sloane Square, on September 28. For more information, please go to grangeopera.co.uk.