While the clouds are being cracked open like eggs overhead, the rain slopping down onto the hot skillet of this valley floor, it is a good time to sneak in some writing!
We have been working hard to grow potatoes these past 5 or 6 years. This soil is listed in the soil survey book I have as "not suitable for agriculture," and if agriculture means plowing and planting of field crops, I would be tempted to agree with that. It is rocky, the topsoil is shallow, the drainage is poor, it tends acid. Hm. Potatoes are not the first crop that comes to mind, since they like reasonable organic matter, excellent drainage, moderate pH, and rocks are a hassle when digging potatoes.
However. Through a variety of circumstances beyond the land's control, we have come to live here, we bring with us a drive to produce our diet from this place, and we like potatoes. So.
Knowing the problems of soil erosion in this culture, and knowing potato digging implies bare soil for a few weeks (an erosion risk), it seemed wise to us to select the site on our slope with the least erosion potential when choosing where to grow potatoes. That leaves two possibilities, one larger, one smaller, as places with no built or natural obstructions and of minimal natural slope. The larger of the two has been selected by us as our "root patch," and now that it's fenced in we can expand the variety of roots we try to grow there, since critters can no longer dine on our sweet potato vines and carrot tops. It seemed sensible to us to group our crops that grow underground and require digging into one growing location, since the soil qualities necessary to promote their health share a lot in common and the erosion risks associated with them are similar.
But the diversification of subterranean crops in the root patch is just beginning with the planting of 70ish sweet potato slips and a few peanuts in the garlic beds this spring, so as far as edible roots from our root patch, potatoes are still where our focus has gone. And that's been challenge enough! With low organic matter, it's pretty hard to work up much soil, especially in shallow-topsoil situations. Plus, soil working tools keep bouncing off the rocks! Add to that the drainage problems causing the plants to crowd their tubers near the surface (increasing toxic greening of skins) and pH stress, and our yields of edible potatoes have been--I admit it--paltry. We've always had enough to make a difference in our winter diet, but never as many as we'd like for this growing family. Further complicating matters is the weed seed load which is still high in that soil and the fact that we've used potato planting as our excuse to bust the original sods and the sods of weeds that re-form; I'll concede the arduous-work to sweet-reward ratio has been less favorable than would be ideal.
On the horizon, however, I could always see that fair country wherein we trench the rows without incident, apply biochar to the floor of the trench, pull in some of the loose soil, lay in chunked seed potatoes, cover, wait for sprouts to appear, pull the rest of the excavated soil around the stems, wait another few weeks for rampant growth to surge, work up a few inches of light, rich topsoil to hill against thick, firm stems at the base of a broad top of wide, dark-green leaves (plucking the odd rock from the soil as it shows itself), then mulch with freshly cut grasses from the surrounding pastures. To top it off, we'd come back with watermelon seed to tuck into the rows here and there for an extra treat in August, and poke in a few handfuls of innoculated black bean seed as a companion crop, one row down each side of the hilled potato rows.
Friends, it is my honor to announce that after several years of hard work--sod busting, rock picking, soil working, row trenching--in that direction, that fine day has now arrived! Friday's job was to do the last hilling on the potatoes, apply mulch, and try to get the companion crop seed sown before this weekend's rains. This is the first year that we've actually brought potatoes back--after three years of absence--to a soil that had already had most of the rocks cleared from it, had had most of the perennial weeds eliminated, had had most of the woody roots removed, and had been cared for for several years with minimal tillage and cover cropping regimes that have built organic matter and soil tilth. I won't claim it wasn't a hard day of work, but the fact is it was doable and the results were visually rewarding. I have every reason to think we'll get a much better yield, too! The plants are bigger and greener than ever, the hills are higher, the biochar is fully charged and doing its drainage work...we are ready to roll!
Using hand tools for heavy gardening tasks like this yields many interesting insights. One is a sense of how and where and in what direction force can most judiciously be applied to get the needed result. Another is an extension of Fukuoka's guiding agricultural question, wherein he asks--instead of "What if I did this or that?"--"What if I didn't do this or that?" When your body is going to do it or it won't be done, you get in the habit of coming up with systems that require less intervention, which is better for the soil and the ecosystem in general. A third insight in this case was just how much difference "good" soil makes when gardening by hand. The lighter, more friable soil we had to work with this time around was probably twice as easy on our bodies and the job took probably two-thirds as long. Three cheers for Organic Matter!
In all ways, things seem to be looking up in the potato patch. I frequently tell Kali when we're working that soil together that she is going to be the only one of the kids who remembers how tough it was at the beginning. For the younger ones, it will seem as if this potato ground has always been here, that the good soil was just waiting to receive their spud chunks each spring and couldn't wait to be pulled up into a rich, dark turtleneck around each of the thick, turgid potato stalks. Tubers rolling out of the soil by the bushel in September will seem normal to them (we hope!). If this system continues on its current trajectory and is maintained by wise and responsible gardeners, there is no reason it shouldn't keep getting better and easier every year. If any of our children continue to choose this place for their home, it warms my heart to think of generations unborn coming to this same soil every spring and fall to trust it with their seed and claim their harvest. May the work we've invested benefit them as much as or more than it has us, and may their joy in using the patch match or exceed our joy in its development!
P.S. For the garden geeks, here's the system: The patch is on a four-year rotation (which I won't describe in detail here...ask if you want to know!). 96 feet long and 12 feet wide, nestled between planting strips that hold or will hold a variety of perennials anchored by grapes and blackberries and with insectary plants mixed in. Historically we've used wide rows laid out on a three-foot increment (two feet for planting, one for walking paths) for the 12-foot width, but we've just gone to a 4-foot increment (three feet for planting, one for walking) with the potatoes this year. A trench is dug roughly four inches wide, and as deep as doesn't feel ridiculous or unearth gobs of subsoil (a little is desirable...we're trying to deepen the drainage and eventually the topsoil layer, but don't want to overdo it in any one year). An A-frame level is used to ensure that the bottom of the trench won't puddle water but will allow for a gentle flow from one end to the other. We use a slope of 1.5 to 2 inches per six feet for our average. Biochar that has been acting as the effluent filter under our Humanure compost pile for two and a half years or so is added to these trenches in a roughly two inch layer. Loose soil from the trench digging is pulled in until the biochar is covered, then potatoes are seeded about one per foot in the row, pressed into the soft soil slightly. More loose soil is pulled in to cover the propagules, but the soil level is still about two inches below original most places. After sprouts appear and are about 6 or more inches high, we pull the remaining loose soil around the stems to support them as they take off. If the char is charged well, take off they will! Then when the vines are about a foot above that soil level but still upright and stiff, it's time to loosen soil from between the rows and hill it up against the plants in a long hill. We use a wheel hoe with ripping point (we contrived this one) and garden plow attachments for the bulk of this work, which was accomplished this year in two rounds. For each round a hand hoe was used to pull stray loose soil from out of the paths and do the detail shaping of the hill and tucking soil around the stems where there were voids.
Scythe-cut hay grasses from the pastures were then used to mulch in a 4-6 inch layer in the paths, tapering to zero at the tops of the hills. This pattern combined with the four-foot increment permitted all mulching to be done with forks instead of hands, avoided any detail mulching around the plants (they make their own shade), and allowed the addition of watermelon (experimental) hills every six feet down the middle row, plus two Black Turtle bean seeds pressed about 3/4 inch deep between each potato plant on each side of the hill just on the shoulder of the hill before steep sloping begins. To clarify, this means roughly 4 Black Turtle seeds per foot of potato row, the beans sown in a double row (10-12 inches apart?) that straddles the potato row. We used maybe one cup of beans for the whole patch. The bean plants are purported to repel potato beetles, and potato plants are purported to repel bean beetles. I won't vouch fully for the bean beetle reduction, but using this system we've had extremely little potato beetle pressure. Could be the mulch, could be the beans, could be diligent scouting and smooshing in years past has reduced the population...I don't know. Black Turtle has emerged as our favorite bean for this polyculture, since the upright plants help support the potato vines, which is supposed to increase yield. Plus, the pods of this variety are not often found against the soil at harvest time, reducing mildew and moldy bean issues, which means less sorting for us! They also thresh out wonderfully by hand. Pinto works ok, too, but the vines are more floppy. Tongue of Fire is an intermediate option, but the heavier beans sag the plants even though they start more upright than Pinto. We don't know our potato variety, which we got from a friend once, but it is an ordinary white potato such as Kennebec. There you have it!
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