They used to just feature at school sports days and village fetes but the gazebo has become a must-have garden accessory this spring as preparations for gatherings at Easter prompt sales of garden furniture and accessories to go “crazy”.

Garden furniture, gazebos, outdoor pizza ovens and fire pits have been flying off the shelves in recent weeks as families prepare to reinstate their social lives outdoors under England’s “rule-of-six” Covid restrictions, which restart on Monday.

Argos and John Lewis are among the big names warning customers of stock shortages. The coronavirus pandemic is still causing major upheaval in the global shipping industry, and the situation could worsen in coming weeks because of the blockage of the Suez canal by the stricken container ship Ever Given.

A notice on the Argos website states that “due to high demand we are running low on garden furniture”. John Lewis has sold out of all but eight of the 71 garden sets listed on its website, but says “more stock is expected end of April”.

The Leisure & Outdoor Furniture Association said retailers were dealing with a perfect storm of soaring shipping costs and delays to shipments, at a time of runaway demand from consumers who have been stuck at home for months. Of the current shortage of garden furniture, a spokesperson said: “It is not like it is not coming but there is a delay.”

On top of that, sales have “gone crazy” as shoppers try to buy early and so avoid missing out, with their hopes of foreign getaways this summer starting to fade. She added: “Sales have gone through the roof. Everyone I have spoken to has either met their budget already or gone way above it.”

The spending spree by excited households in the run-up to next week’s relaxation of rules on outdoor socialising in England even showed up in official retail sales figures published on Friday, as unseasonal demand for the patio sets and DIY materials needed to create “outdoor rooms” propped up a high street that is reeling from the third lockdown.

The online DIY marketplace ManoMano said sales of gazebos last month were almost seven times higher than in 2020, as Britons prepared to reinstate missed Christmas get-togethers with friends and family, and protect themselves from further cancellations if it rains. ManoMano’s range spans budget-friendly gazebos favoured by campers, for less than £40, to more than £4,000 for a solid wooden structure complete with a bar to lean against.

The desire to create “outdoor rooms” has resulted in a near-600% increase in demand for fire pits and outdoor heaters on the trading site eBay, which has also reported shoppers scouring listings for six-person hot tubs as well as outdoor bars and projectors. “Easter trees” and wreaths are also being bought to dress gardens.

The kitchenware chain Lakeland said super-fast pizza ovens, such as the £300 Ooni Karu, which can be readied in 15 minutes and cooks a 12in pizza in 60 seconds, were also selling fast.

The lockdowns of the past year have translated into big profits for DIY chains such as B&Q, whose stores were permitted to stay open. It estimates that homeowners had devoted 31 days in the past year to house renovations and garden improvements. Sales of decorative items such as outdoor rugs were up more than 10%, while demand for statement outdoor tiles has increased fivefold. Fairy light sales were also up 56%.

At the furniture chain the Cotswold Company, where sales of garden products are running 600% up this year, its chief executive, Ralph Tucker, is nervously watching a tracking app that shows the growing traffic jam in the Suez canal area: “If they can get the ship off the sandbank today that will cause a week or two of issues in the supply chain. If it is there for a week that could cause months of issues.”

Lifestyle changes ushered in by pandemic restrictions mean Cotswold’s shoppers now want big outdoor furniture sets, rather than bistro tables, and even chunky pub garden-style trestle tables, Tucker said. The Manchester-based businessman, who has just erected a gazebo in his garden, said the shelters enable households to have nicer furniture outdoors as well as outdoor kitchens or cinemas.

Retailers’ gazebo ranges include “luxury” options with blinds or doors and built-in lighting. There are also trendy aluminium frames with sliding roofs that can cost as much as a summer holiday.

“We’ve got a bit of a roof because we wanted it to be practical; it does rain a lot in the north,” Tucker said. “Consumers see the outside as somewhere where they are going to entertain, not just when the sun is shining.”