The United Kingdom's Royal Botanic Gardens, Kew, in London have been a place of reflection and natural refuge for about 250 years, though now they sit empty because of the country's coronavirus pandemic lockdown. On April 22, as we celebrate the 50th anniversary of Earth Day, Kew Gardens' director Richard Deverell warns that more "fundamental challenges" could lie ahead for humankind "unless we start to treat the natural world better."

"It's exceptionally beautiful, but it's tragic to see these beautiful gardens, 330 acres here at Kew— a world heritage site— to see them empty," he told CBS News' Mark Phillips.

Deverell, who also lives on the property, said he "hopes" the current situation could help people understand the importance of respecting nature.

"We've got a situation today where four and half billion people are in lockdown, that's extraordinary," he said. "So I hope, if nothing else, this COVID experience has given us a dose of humility… we are just one species of many, many millions."

He added that we "need to play our role" alongside Earth's other species "in a responsible way."

"And I hope too, that we'll realize that actually the cost of pre-empting a problem, of mitigating it, is a fraction of the cost of dealing with it when it engulfs you," he said. "If you abuse the natural world, bad things happen, including bad things to people."

Researchers at the gardens are already working on these mitigation efforts. With new specimens arriving from all over the world, scientists are studying ways to help plants cope with a warming globe.

Among others projects, researchers are studying how to deal with coffee beans that are not getting enough rain and getting too much sunshine.

The team is working to find varieties that are more tolerant to the changing conditions.

"Perhaps some have greater heat tolerance or aridity tolerance that can be bred into the commercial crop to safeguard future supply of coffee," Deverell explained.

Deverell highlighted the importance of keeping nature safe and in tact not just for the natural world, but for humanity itself.

"At the simplest level, of course, plants provide us with oxygen," he said. "About a quarter of all cancer medicines derive from plants and fungi, so they deliver many, many beneficial things to humans."