Outdoor garden attractions have expressed their frustration over “no-shows”.
The National Trust, Kew Gardens and the Royal Horticultural Society (RHS) said their members were booking slots to visit and then cancelling or not turning up.
The attractions are free for members but people have to book in advance in order to maintain social distancing.
Kew Gardens said as many as 40% of those booking were not turning up.
“It’s really difficult for us because so much of our income relies on visitors coming to the gardens, paying to get in, their memberships, eating and drinking on the site, or buying something in the shops and that all has an impact,” said Paul Guthrie, from the botanical gardens in west London.
“We’re sympathetic to why it happens, plans change, weather changes, but in these times we’re particularly asking people to cancel their bookings wherever possible.”
Members’ tickets cannot be reallocated when they fail to turn up.
“It’s a real shame because that could be space for someone else to be visiting,” Mr Guthrie said.
Currently Kew Gardens can safely accommodate 8,000 people each day.
Before social distancing, a busy summer’s day would have seen between 10,000 to 12,000 people pass through its doors.
The gardens are facing a £15m shortfall compared to last year.
Sally Charleton, director of gardens at RHS, said on days when the weather was poor, the no-show rate could be as high as 20% across all of its gardens.
“Those who don’t take up their booked time slots are RHS members who already support the charity through their membership fee and are able to visit our gardens for free as a member benefit,” she said.
“However, in order to ensure that we can also welcome as many non-members as possible, we have increased our daily cap on visitor numbers to account for no-shows, whilst still keeping within safe limits.”
The gardening group said limiting visitor numbers had seen it cut the number of people that could attend drastically.
On a peak summer’s weekend, 8,000 visitors would have attended RHS Wisley in Surrey, whereas now it is capped at 4,500.
The National Trust said it could not provide exact figures but it was “unfortunate” when members did not turn up as it meant others could not visit.
It encouraged people to cancel bookings with at least 24-hours’ notice.
Other industries, in particular the restaurant industry, have also said they have been affected by no-shows.