It began with a farmer who wanted to see how his neighbours had weathered a deadly cyclone. It has turned into an extraordinary grassroots relief operation that has helped thousands in rural Mozambique.

Helicopters land in the farmhouse's driveway. Aid workers in matching T-shirts sleep in tents in the front yard and on the roof. Hundreds of local subsistence farmers whose lives were swept away by the floods drop by to collect the food and supplies to start again.

"We've been at it for ... three weeks? I've lost track of time," the farmhouse's sole resident in normal times, said mango farmer Gilles van de Wall, after another frenetic day.

Potluck reigns. Visitors bring beer and bottled water to stock a straining refrigerator. Dogs, at least one cat and a caged grey parrot have adapted to the crowd. New people arriving? Just budge over.

"Prepare to be utterly disappointed," one recent night's impromptu cook for the crowd of volunteers declared.

Cyclone Idai hit this part of rural Mozambique particularly hard, with torrential rains draining down from the nearby mountains that separate the country from Zimbabwe. Rivers burst their banks leaving corn stalks hanging from electrical wires.

The floodwaters made the farmhouse and surrounding buildings an island. Even before the waters drained, Mr Van de Wall began a rescue operation for families nearby, "then a much wider area," he said. Soon, some 600 people were sheltering at the farm. Then 1,000.

The first night he did not get much sleep because all the children were crying, he said. Then more food arrived to ease their hunger pangs.

Word got out among fellow large-scale commercial farmers. Friends from the nearby city of Chimoio brought the first supplies. Then others came from Mozambique's capital, Maputo, 1,100 kilometres (680 miles) to the south. People started driving up from South Africa, even farther away.

Meanwhile, workers at the farm were reporting distress in communities across the crocodile-inhabited Lecito River behind the farm. Remote by road — a 150-kilometre (93-mile) drive — and yet just a kilometre (mile) across the water, the communities were judged to be in "critical" need of help, Mr Van de Wall said.

The opening of the road some five days after the cyclone helped to reach them. The arrival of helicopters helped even more. Tons of food, shelter and utensils, mostly from donations, were flown in.

"If you're the first people to reach them, it's indescribable," Mr Van de Wall said of the desperation of families surrounded by flooded fields.

The emergency assistance worked well enough that people on the other side of the river are living on their own destroyed plots, not in camps, a key factor in avoiding the spread of disease, he said. Scores of thousands of people displaced by the cyclone across central Mozambique are now huddling in shelters, often with poor water and sanitation, and a deadly cholera outbreak has been declared.

Eventually, word about the homegrown relief operation filtered out to aid groups hurriedly trying set up operations in the cyclone-hit region while roads were repaired and waters drained. Many needed somewhere to sleep, eat and get marginally clean.

"Hundreds of people have stayed here," Mr Van de Wall said. "There were 30 to 35 a night last week. Before that, 10 to 20. Before that, it was me and my neighbours."

And like clockwork, every time they ran short of something, it would turn up, he said.

The farmhouse relief effort was so desperate to fly supplies to inaccessible areas that when the governor visited they commandeered his helicopter to deliver food, Mr Van de Wall later told visitors at the nightly briefing around a bonfire in a wheelbarrow. A few were nervous that the governor would finish his speech and want to fly away before they returned the aircraft, he said.

Aerial view showing aftermath of cyclone Idai's course through Mozambican city of Beira

Then the briefing turned to the daily report: 11,000 kilograms (24,000 pounds) of rice distributed on Thursday across the river. More than 2 tons of supplies delivered on this side.

"It's an amazing operation you've put together," a member of a visiting international medical team told the group.

Seventeen-year-old Pieter Botha, the son of the farmhouse's owner, Kobus, has watched the organised chaos since arriving a week after the cyclone from Maputo to help out, and who had been loading helicopters that day.

"Everyone here is strangers," he said as people wandered in and out the front door or held planning meetings on the lawn. "Everyone who arrived just wanted to help. It's a very friendly environment. It's fun."

The aim has been to provide nearby subsistence farmers with a month's worth of food until Mozambique's government and the United Nations' World Food Programme could get longer term relief deliveries up and running, Pieter said. The cyclone wiped out crops that were just weeks away from harvesting, so most families will need nearly a year's supply of food, aid workers say.

The makeshift rescue effort has helped almost 9,000 people so far, Pieter said.

"It's on the board!" he insisted, gesturing to a whiteboard propped near the porch, scrawled with a rough map of villages and the numbers of residents.

The relief effort appeared to be working. Dozens of Mozambican women gathered nearby for boxes marked with the logo of USAID that contained cooking pots.

"Everything was washed away," one waiting woman, Rosita Cuanda, said. "The goats, the chickens, the house. We were left with nothing."

Mr Van de Wall's farmhouse has been the central point of help for community members, she said. With the aid distributed they have been able to feed their families, she said, counting off 10 relatives of her own, but shyly saying she could not remember her age.

Her family had a long-standing relationship with Mr Van de Wall because they help to harvest his mangoes, Ms Cuanda said: "We know him well."

Hundreds of strangers brought together by disaster now do, too.