Life on Christmas Island: Turning mining sites into farmland

There was a perception that nothing could be grown on Christmas Island and locals would have to continue to endure exorbitant prices for fruit and vegetables. But a team of agricultural specialists is proving that wrong.

Scientists and farming specialists have grown tonnes of fresh produce on Christmas Island on land that many locals believed would never support plant growth.

The experiment has proved so successful that the proponents are confident it could be turned into a commercial agricultural enterprise by the end of 2016, adding a much-needed boost to the local economy.

It could also pave the way for cheaper fresh fruit and vegetables on an island where a lettuce that has to be flown in can cost up to $18.

The project, supported by the federal government and Christmas Island Phosphate, has been dubbed MINTOPE: Mining to Plant Enterprises.

The project has taken former phosphate mining sites, which lack the most basic of nutrients and materials, and turned them into arable land capable of supporting a variety of crops including legumes, cereals and vegetables.

Murdoch University sustainable agricultural specialist John Howieson spent years analysing the soil and testing out varieties of plant species including African lablab beans.

The ground was so compacted by decades of heavy machinery that a chisel plough was necessary to break it up.

“I was very excited because, of course, before we got there the mythology was that we couldn’t grow any food plants,” Professor Howieson said.

“People had tried over the years and inevitably failed for one reason or another.

“So once we established the limiting factors to plant growth, it was really exciting to see the rapidity, denseness and lushness of the growth of the legumes.

“We grew something like 30 tonnes fresh weight of lablab in seven weeks because the temperatures are perfect. It rains regularly and our cultivation of the soil allowed the soil to hold that water for the couple of days a week it doesn’t rain and plant growth was perfect.”

But before the team began planting, it learnt the soil was chronically lacking in carbon, nitrogen and potassium – all vital elements for soil fertility.

That’s where the legumes came in along with rhizobium bacteria.

“Legumes are plants that if they have the right bacteria in the roots can take nitrogen out of the air and turn it into proteins,” Professor Howieson said.

“So they can take the nitrogen and form their own proteins and become independent of the nitrogen status of the soil.

“All we had to do was take over a simple fertiliser of potash, which is cheap and quite easy to move around, so all we’ve taken to the island is potash, legume seeds, and rhizobium inoculate.

“And with that we’ve worked out how to grow the legumes first, they improve the fertility of the soil by putting in nitrogen and carbon, and after the legumes we’ve rotated with the cereals such as maise, sorghum and millet.”

Sorghum crops still growing strong despite no rain for months.

The team also grew peanuts, pumpkins and chia.

At an open day in mid-2015, the MINTOPE team invited the locals to an open day to see for themselves how barren, dusty mining land had been turned into fertile soil supporting hectares of crops.

The locals also enjoyed the first harvest, taking ears of corn that would cost about $10 each for free.

Another round of planting will begin in early 2016 and the team is looking at growing feed for livestock as well in an effort to create another industry for the island that mainly relies on phosphate mining.