Although a great swath of the UK’s restaurant terraces and pub gardens opened in mid-April, if you’re anything like me, you will have tried a half dozen places and duly failed to nab a reservation at any of them. The only way forward, in my opinion, is to start dining alfresco in the parks, gardens and hills of this green and pleasant land.

So to our picnic blankets we trundle, but what to wear once we’re safely ensconced, Scotch egg in hand? For sartorial inspiration, there’s the immortal moment from 1955’s To Catch A Thief, when Cary Grant and Grace Kelly stop for an in-car sarnie on the road between Nice and Monte Carlo, Grant clad in one of his favoured charcoal flannel suits and a navy blue cravat.

And then there’s the sweeping mid-safari picnic from 1985’s Out of Africa, in which Meryl Streep and Robert Redford share more furtive glances across their enormous linen blanket than they do bite-size snacks. The latter’s white jeans and green corduroy overshirt get-up is a thing of outdoorsy excellence — potential grass stains notwithstanding.

When it comes to your own trans-seasonal picnic outfit, a good place to start is with your base layers. Swedish underwear brand CDLP’s understated T-shirts are crafted from heavyweight lyocell and Pima cotton, and are surprisingly insulating.

A bright, oversized shirt of heavyweight Oxford cotton would be my suggestion for the next layer up. One of the preppy Oxford styles from Polo Ralph Lauren (£115, ralphlauren.co.uk), Drake’s (£175, drakes.com) or Japanese brand Beams Plus (£175, mrporter.com) will both look summery and, if worn under a jumper, keep that all-important, prosecco-induced heat inside your body, where it belongs.

On the subject of sweaters, there’s an excellent Sebastian Flyte-infused appeal about the periwinkle, powder pink and heather jumpers from Californian knitwear brand The Elder Statesman (£695, mrporter.com), while Tom Ford does an excellent lilac crew neck jumper crafted from fine-gauge Alpaca and silk (£670, mrporter.com).

On top of that, my recommendation would be to invest in a souped-up take on a chore jacket. British menswear label SMR Days has a wonderful embroidered option in faded cobalt cotton (£325, smrdays.com), while for something a little warmer, Italian brand Aspesi and Mr Porter’s in-house label Mr P both do smart versions of a chore jacket in corduroy (£412, farfetch.com; £195, mrporter.com). The latter offers one in a delicious shade of teal that will look appealingly cheerful with your lilac cashmere under-layer.

On your legs, it’s got to be a pair of Redford-inspired white jeans. High street brand Arket is a good place to go for a pair on the more affordable side of the picnic blanket (£69, arket.com), while Jil Sander’s straight-cut white carpenters are (expensive) denim perfection (£460, matchesfashion.com).

The final flourishes to your outfit should be sunglasses (Persol’s new Steve McQueen special editions are both chic and masculine, £319, persol.com) and a blanket. The best of these can be found in classic tartan at Fortnum & Mason (£110, fortnumandmason.com) and in snazzier patterned terry cloth at Pendleton (£120, mrporter.com).

You could take it a step further with a fashion blanket from Raf Simons (£440, matchesfashion.com) or Loewe (£450, loewe.com), draping it extravagantly in the style of a shawl to mitigate the fact that you’re drinking fizzy grape juice from a plastic glass while sitting on the cold English ground, as opposed to chowing down on a mortadella panuzzo on the Grande Corniche. Sigh.

Teo van den Broeke is style and grooming director at GQ magazine

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