July 16, 2015
This is the second part of a two-part interview. Read the first part here.
Is combining organic and mineral fertilizers better?
“It is probably best in most agricultural situations in the world to combine mineral with organic fertilizers. Most farmers add manure in addition to mineral fertilizer. The plant doesn’t care whether that nitrate or phosphate ions it take up comes from a decomposing piece of manure, a decomposing leaf or mineral fertilizer. The plant only takes up those ions from the soil and it doesn’t matter whether it is from organic or mineral fertilizers. So the combination the combination is the best.
You want to take advantage of the carbon and micronutrients in the organics, but often organic fertilizers cannot satisfy the plant´s nitrogen needs. You can supply a lot of nitrogen very quickly by applying mineral fertilizer.”
What would happen if the world “went organic”?
“Suppose the world goes totally organic, using organic fertilizer only, the estimates are that the world may support a population of about 3 billion people. We already have about 7.5 billion people today and we are heading towards 9 or 10 billion. Organics certainly cannot feed the world by any stretch of imagination. Furthermore and in order to grow those organics there would need to be a tremendous amount of additional deforestation that would result in incalculable environmental damage to biodiversity and more greenhouse gas emissions. So that is not an option.
People claim that they don’t have the scientific facts. A lot of them are guided by their enthusiasm for organic agriculture, which is scientifically fine, if it provides all the nutrients, farmers are able to cope with the additional labor and can sell their produce at premium prices.”
So it is a matter of science versus values?
“One needs to be diplomatic and empathetic with people who strongly believe that organic agriculture is the only way to feed the world, but science will win on this issue, as it has done on many other issues."
Is organic fertilizer more environmentally friendly than mineral fertilizer?
“They are equally environmentally friendly if they are both applied at the right rates at the right times. There is no advantage of either one or the other. Excessive use of either can damage the environment like in China now and like in the U.S. and Europe a few decades ago.”
Does excessive use of fertilizer poison the crop?
“No, but using fertilizer at excessive rates is harmful for the environment. Fertilizers, even excessively used, cannot poison the soil. Fertilizers do no damage whatsoever when properly applied but as with everything else, if you apply in excess you get into serious environmental problems. My message to the fertilizer industry is make sure farmers apply at the right rate and at the right time so that you don’t run the danger of messing up the environment with excessive applications.”