organic vs. conventional potatoes

I’ve been grading papers for the university classes I teach.   A student of mine is the son of an Idaho farmer, and he makes a case that organic produce is not worth the money.   This is one of his arguments (edited for length):


“Technologies developed in recent years are amazingly efficient.   For instance, a potato field requires 400 lbs. of nitrogen per acre.   Modern technologies have developed fertilizer that contains 60 percent nitrogen and 40 percent additional fertilizers in a petroleum-based liquid for easy spraying.


“Contrast that with the method of organic farming, using manure to provide nitrogen.   Manure contains only about 10 lbs. of nitrogen per ton.   This means 40 tons of manure must be applied to each acre of potatoes to supply needed nitrogen.   That equates to a layer covering the whole field five inches thick!”


He then makes the case that farming with petroleum-based sprays is more efficient.


Potatoes a la Petroleum, anyone?   Your thoughts??

12 thoughts on “organic vs. conventional potatoes

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  1. It probably is, for the farmer, as farms are much larger and commercial than they were 100 years ago. Unfortunately, our food supply has proven fallible and we’re now seeing the results of these polluting fertilizers in our food. I’d rather plant a small square in the backyard, thank you very much. My thoughts are that God created the cow and thus the manure, so I don’t have a problem with it. It’s the chemicals and GMOs that are the problem.

    What classes do you teach?

  2. It may be better cost wise for the farmer but what about humans having to eat the petroleum-based liquid? How much is good health worth?

  3. No body says it better than Michael Pollan. Read his books, In Defense of Food and The Omnivore’s Dilema.


    I’ve heard that Thai coconuts are pesticide laden. Do you have a source for organic thai coconuts on the mainland.



  4. I’d be surprised if they have much pesticide, since it’s mostly indigenous people knocking them out of giant trees. They’d need an airplane to spray them. Also, there’s two inches of fibrous stuff to cut off a baby Thai coconut, and then a hard shell, so I don’t know how any of it would even get into the coconut and liquid. ?? Also, even though they’re called Thai coconuts, they come from the Phillipines, Fiji, and other places as well. Interested in your source if you remember it, because I’ve never read that.


  5. Anyone like some Monsanto seeds? Check out all the organic folks against them on the net. I’ll take poo over petroleum. They probably are using GM seeds, too. I understand the farmers plight of having a better yield and crop…but organic crops do better. As long as they are NOT organic they are subsidized by the government. Farmers like that are caught between a rock and a hard place. I prefer to stand ON the rock. Ha! Poop please.

  6. We went to Fiji last year and had a wonderful time. Coconuts are all over the place and it really is many indigenous people knocking them out of trees and splitting them on a rock or with a machete. Amazing how quickly one of our guides was able to break those babies open. They were so good….so was the fresh pineapple we had with everything. Fiji is an amazing place and people and I wish I could live there.

    Tangent over 🙂

  7. Robyn, you’ve said previously we don’t have to buy organic produce (since for most people it’s too expensive), but this post implies that we should at least be buying organic potatos, no?

    based on various recent references to your past and present “occupations” (counselor, college teacher, etc) ….is there anything you HAVEN’T done?! wow – if I start eating like you do, will I be able to do all that too?! :o)

  8. Well, let me clarify about my position on organic. In a perfect world, everyone would buy everything organic. But it’s not a perfect world, and I would rather see people buying conventional produce than all the other choices. The worst-case scenario is that people are scared of pesticides to the extent that they just don’t eat vegetables and fruits. I think we have to take some comfort in thousands of studies that show the benefits of eating these plants–most of which are CONVENTIONAL, not organic. We do the best we can with the dollars we have, we WASH IT ALL WELL, and we expect that food to nourish us well and bless our lives.

    So, do this with the potato story: (1) buy organic if it’s not cost prohibitive for you, in your circumstances, (2) if you can’t, scrub those potatoes well, (3) teach others and sound off anywhere you can about how we want produce grown and stored without chemicals–maybe the big conglomerates will get the message as there is strength in numbers.

    Re: all my professional pursuits, ha, YES, eating right gives you the energy to live your dreams, do things you never would have otherwise been able to do!

  9. I asked my son to reply to this young man. My son is the manager of an organic fertilizer company in the Idaho Falls, Idaho area. He has a Bachelor of Science degree from BYU, ID. Their primary customers are potato growers…which is increasing every year because of their profit margin is increasing.

    First thing I would say is that this young man sounds an awful lot like me when I was in college. I wasn’t convinced of organics either. In fact I wrote several papers against organic farming. Most of the information I used for my papers were taken from very biased sources. After being involved with an organic fertilizer company; in Idaho I might add; you could say that I have “seen the light.”

    The first argument I would make is that the organics game has become “amazingly efficient” also. The days of just throwing several inches of manure on the ground and letting the crop grow are long over. In fact I don’t know any organic farmer in the state of Idaho that uses straight manure. Now compost…that’s a different story.

    The next argument I would make is that potatoes need 400 lbs of nitrogen per acre. Wow! That’s a lot of nitrogen, especially in the form of a petroleum based chemical. Although it doesn’t surprise me that some farmers apply that much. After years and years of using petroleum based chemical fertilizer they have pretty much destroyed most of the organic matter in their soil along with all the beneficial microbes and other trace element that the plants need.

    Bottom line is this. First, most organic farmers don’t use raw manure anymore. They use composted manure. Big difference between the two. The compost process allows the manure to be broken down into pure organic matter. Which has a much higher nutrient value than manure. A good compost will have about 22-27 lbs of nitrogen per ton. This is a big difference from the 10 lbs per ton from the raw manure. With compost you’re not only getting nitrogen you are also getting about 35 lbs. of phosphorous per ton and 67 lbs per ton of potassium. Not to mention many other trace elements such as sulfur, magnesium, calcium, iron, manganese, copper, zinc, boron, and humic acid. All of which are extremely important to the plant. Most conventional farmers spend so much money on nitrogen, phosphorous, and potassium (NPK) that they don’t have enough left over for the trace elements.

    Now on organic potatoes we put down about 15 tons per acre. Which is about 1/2 inch thick. Also, we don’t rely on compost as the only source of Nitrogen. Throughout the growing season we add several different types of organically approved liquid fertilizers to potatoes so that we don’t have to rely on compost as our only source of nutrients. We also get a residual affect from compost. Because it is a natural form of organic matter it stays in the soil which also helps for the next years crop….that is until the next farmer comes along and decides to put a petroleum based chemical fertilizer on the field, in which case it would destroy most of the organic matter and beneficial microbes.

    Besides compost being a good nutrient source it also has other benefits. Such as water holding capacity. Farmers have found that they use less water on their organic crops than they do on their conventional crops. On average about 25% less, and as much as 35% less.

    Anyway…I could continue to go on and on about the benefits and misconceptions of organic farming, but I hope this shows that if you want to know the truth about organics talk to someone who knows about organics.

    Oh by the way another misconception is that organic food costs more to produce. Not true. We can grow a crop of organic potatoes for about the same cost as a conventional crop, sometimes even less. This gives an organic farmer a much higher profit margin because organic food sells for more. It sells for more because of supply and demand…and thats a whole other debate.

    1. Thank you for all that information on the growing of the potato. I’m putting together a cookbook for my daughter for a Christmas Present and come across this . Love it !

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