Further to my recent article on how rising food prices will be good news for rural communities all over the world, The Land newspaper has carried an interesting report on how rising energy and fertiliser costs (Nitrogen is now $1000/tonne) have restored and reinforced the economics of growing nitrogen fixing cover crops in fallow rotation.
Cotton farmers routinely add 200kg of nitrogen/ hectare but the growing and ploughing-in of Vetch in rotation has been found to add 140kg in a more balanced application that is safer for the following cotton crop in dry times. It substantially reduces cash outflows, leaving the synthetic form of this fertiliser as an ‘opportunity outlay’ to boost production in a good year. It seems the humble Fava Bean is almost as good for this purpose, with the advantage of producing a cash crop as well.
The implications of this, not just for farmers in less developed nations, is that they have the means to boost production in response to higher world food prices without placing additional demands on world oil/fertiliser supplies. In poorer countries the input cost is no more than the price of seeds and the farm family’s own labour.