Why, again, do Afghanistan's farmers grow poppy? This is a bit more granular than our last post.
Poppies pay. That's according to a 2012 chapter called Counternarcotics efforts and Afghan poppy farmers: Finding the right approach (pdf) by David Catarious and Alison Russell.
When the Taliban (pretty) successfully outlawed poppy growing in 2000-01, many farmers in Afghanistan switched to growing wheat, which doesn't provide nearly the same income levels. Wheat is also less labor intensive than poppy, which put a lot of farm hands out of work. For those remaining in cultivation, aid and international development did not make up the earnings gap.
This creates a ripple effect throughout the non-drug economy. A 2005 International Monetary Fund report (pdf) claimed that poppy farmers took home one-quarter of the estimated $2.3 billion of the country's 2004 drug income. This money is quickly filtered throughout the rest of Afghanistan's legal economy. (On the other hand, opium processors and traffickers -- the other members of Afghanistan's drug economy -- spend much of their funds outside the country.) The illicit economy and legal economy in Afghanistan are so intertwined, the IMF warned in 2005 about economic consequences if eradication would be immediately successful.
Poppies have a long history in Afghanistan, creating a very knowledgeable workforce. It's long been common for non-land owners to sharecrop poppies to pay rent and provide for their families. (Affording to rent land through drug production also allows sharecroppers to grow food.)
Access to this cash crop also gives farmers access to credit who would probably not receive any loans. This credit comes from opium traffickers, who can trap farmers in a "cycle of debt" to traffickers making it impossible to leave the industry, per a 2010 study. (pdf).
Agricultural reasons play a role in this, too. Poppies grow well in Afghanistan. They like the moist parts of the country, where the average rainfall can be as high as 19 inches/year. But poppies are also more drought resistant than other crops, which is helpful in areas of the country where precipitation reaches only 4-5 inches.
This is also true after harvesting, when the dried latex must be shipped long distances (during hot months) to market.
The poppy plant also provides peripheral products, such as cooking oil, fuel and food for animals.
From the chapter written by Catarious and Russell:
"Finally, their relative hardiness and ability to generate income make poppies work well as a hedge against the failure of other crops. Even if poppy is not their primary crop, many Afghan farmers are willing to include poppy in their field."
Here is the citation, again: D. Catarious, A. Russell. 2012. Counternarcotics efforts and Afghan poppy farmers: Finding the right approach. In High-Value Natural Resources and Peacebuilding,ed. P. Lujala and S. A. Rustad. London: Earthscan.
Linked here. (pdf)