Fans of the royal family drink wine as they camp outside Windsor Castle prior to the wedding of Prince Harry and Meghan Markle in Windsor, Britain on Friday evening. May 18 2018. Picture: REUTERS/Phil Noble
Fans of the royal family drink wine as they camp outside Windsor Castle prior to the wedding of Prince Harry and Meghan Markle in Windsor, Britain on Friday evening. May 18 2018. Picture: REUTERS/Phil Noble

Three British institutions: The royal family, football, and the weather. Only one will guarantee that hard-pressed Brits open their wallets.

Retailers would dearly love the wedding of Prince Harry and Meghan Markle on Saturday to lift the national mood and loosen the purse strings. The event could drive an extra £93.1m of spending across the UK in May, according to Springboard, which tracks shopper numbers. There could even be a knock-on effect from any newfound cheeriness and a potential pick-up of overseas visitors, which could mean another £102.4m of extra sales through to August.

The ceremony starts at 12pm GMT. But it doesn’t end there. At 5.15pm GMT, Chelsea and Manchester United will play in the FA Cup final.

The two together could bring along street parties and barbecues. And that means a huge demand for food and drink. The celebratory atmosphere could extend over much of the UK’s summer, with the football World Cup kicking off on June 14 and running through to the final on July 15.

This couldn’t come at a better time for all kinds of British retailers. After a dismal start to 2018, struggling shops need all the help they can get, and if the stars do align for a decent run of sales that could save those that are in really dire straits.

For grocers, fresh meat and salad have a higher margin than packaged food. A tipple to toast the happy couple can be good for their earnings too. While there’s little profit in standard packs of beer or spirits, wine and craft ales have fatter margins.

Its possible families getting together to watch the wedding might also head out for a meal after, a fillip for the casual dining sector. Pubs, which have been trading more strongly than restaurants, might benefit from the twin events — the government is allowing them to stay open until 1am on Friday and Saturday night. And Brits could snap up new outfits to wear to street parties. Next found that was the case in the run-up to the marriage of Prince William and Kate Middleton in 2011.

There are, of course, those special royal wedding products that retailers roll out, including Wm Morrison Supermarkets’ copy of the happy couple’s lemon and elderflower cake, made in its stores and selling for £7. High street stalwart Marks & Spencer will even rebrand itself as Markle & Sparkle for the weekend.

Saturday’s events aren’t always an easy way to make a fast pound, though, and not all companies will dive in. There will be no repeat of B&Q’s commemorative garden gnomes. They were produced for the last royal wedding and the Queen’s Diamond Jubilee in 2012, but perhaps this home improvement division of Kingfisher won’t have forgotten its experience with the 2014 World Cup, when England-themed gnomes went unsold. Anyway, the novelties might not fit with CEO Veronique Laury’s efforts to streamline the product range.

However, retailers will only see a big benefit if the sun shines. The forecast is for reasonably warm temperatures on Saturday. But if the predictions turn out to be wrong, and the day is colder or wetter than expected, the whole thing could turn out to be rather a damp squib.

Betting on the World Cup to save the day is a tricky one, too. There’s not much of a time difference between the UK and Russia, so many of the matches can be aired in the evening. That’s good for the pub trade, and for supermarkets, as those football fans staying in to watch the games have time to get home from work and pop to the supermarket before settling down on the sofa. And let’s not forget all those flat screen TVs that may be snapped up ahead of time.

These benefits can’t be assured. They hinge significantly on how long England stays in the tournament. B&Q blamed the team’s early exit from the contest in 2014 for all those unwanted novelties.

Hard-pressed retailers and restaurant chains can wish that all the forthcoming events stimulate spending. But without the right conditions — particularly favourable weather — summer celebrations could turn out to be gnome joke.