Stone Soup Farm's Potatoes
A CSA member in Hadley asked me the other day about potatoes. The first question was, "When will we have potatoes?" The answer to that is... soon! Hopefully next week. They're ready now, we just need to set aside the time to dig them up, which we do by hand and it's slower than most things we harvest. The second question was, "Do you spray the vines?" The short answer to that is no, these potatoes aren't sprayed at all, but I wanted to give some more context to that answer.
In Hadley, as in much of the country, there's a lot of big conventional potato and corn fields. The Hadley fields are big by Massachusetts standards (as in dozens or hundreds of acres), but small by national standards (which can be in the thousands or hundreds of thousands of acres). By contrast, the Stone Soup potato patch is 1/2 acre, which is about 6,000 potato plants. Each plant starts with a piece of a cut-up potato planted in the spring, and by this point has grown like 2-6 new tubers of varying size underground, storing the energy that the leaves above-ground have been busy photosynthesizing.
Many organic farms spray their potato plants with organic-approved pesticides (for killing bugs) and organic-approved fungicides (copper sulfate, for preventing plant diseases). Stone Soup Farm doesn't spray the potatoes at all. These organic sprays will increase the overall yield but they don't really work that well, they're pretty expensive, they're a lot of work to apply, and I don't have the expensive nice equipment for it. So with the potatoes I just don't bother.
Conventional farms have a lot more tools at their disposal. Many more options for pesticides and fungicides, and in general the conventional options are much more effective and cheaper. The other big thing they have is herbicides, which kill plants (there are no organic-approved herbicides). Because of their effective sprays over the life of the crop, when it comes time to dig up the potatoes with a big machine, the lush green above-ground part of the potato plant is too healthy and would gum up the machinery if left alon. So it's usually necessary to spray the potato plants with herbicides first, which shrivels up the plant part but leaves the below-ground tubers unharmed and ready to dig.
Luckily for organic farmers, the above-ground part of our potato plants have already withered away due to pests and plant diseases! So digging up those (somewhat smaller) tubers is relatively easy. We also don't have a digging machine.