Here it is late October, and we are still waiting for our first frost to hit. Last year, it came weeks earlier. We just never know what weather Mother Nature is going to toss our way, so as the farmers you’ve entrusted to grow good food for your family, all we can do is prepare. Particularly now that we have an online store, a Fall CSA Farm Share and a Winter CSA Farm Share, we take this responsibility more seriously. Here as the days get shorter, growing into the colder months is on our minds.
We have described in past blog entries how the cooler/shorter days of fall slow the growth rate of greens, with a causative effect of intensifying the flavors within. Basically, the leaves convert solar energy into complex carbohydrates, but the cells do not multiply, therefore the leaves do not elongate as rapidly with the shorter daylight of fall, so all that goodness stays in a smaller package. Even though it has stayed warm, plant growth is primarily dictated by day length, so in the greens to come, you will taste this phenomenon with every bite.
It seems there is no such thing as “normal” weather patterns anymore. It used to be that we figured on last frost about Derby Day and first frost in early October. It used to be that we could count on garden-variety thunderstorms to roll though every so often in the summer, with time to tend the fields and crops in between. Now it’s hard to say when we’ll see our first frost, and lately, it seems like long durations of wet or dry spells set in and hang around for extended periods of time. Our vegetable-planting decisions are based on our collective memory and experience of when is the best time to plant for the fall, but now, we must also plan on moisture and temperature extremes that no one can predict.
In early fall, light frosts roll in and tend to be spotty, with a pattern that has affected harvest in some fields but not others. Overcast skies can block the nighttime radiational cooling that causes frost to form, and the morning fog protects the plants in the lower part of the field, which is where frost normally happens first. If the wind persists all night—particularly important just before daylight—frost formation is also minimized. With all of these conditions combined, summertime flavor will continue until we get walloped with a full frost.
For the Animals
The shorter, cooler days of fall improve the quality of the pasture plants, similar to the effect on produce plants. The sugar content—or nutrient density of the leaves—increases as described above, meaning the livestock consume less to meet their nutritional requirements for growth, so the standing forage lasts longer into the winter. We can actually let fields go ungrazed during September and October, called stockpiling, because the leaf material improves in quality, whereas in the summer, older leaves have reduced palatability and nutrient yield. Stockpiling allows us to graze our cattle and sheep well into winter, as they prefer to graze over eating hay.
Growing into Winter
New growing-season-extension technologies, along with some ingenious uses of old technologies, have helped us strategically plan for the harvest of greens all winter for the past few years. The sunny days keep the soil warm and foster good plant growth until the Persephone days that start in mid-November, when the combination of short days and typically cold temperatures shut down all growth. So the idea is to get plants up to harvestable size before then, where they await harvest in suspended animation until their growth restarts in early February. (The Persephone Days were named such by farmer-author Eliot Coleman. The name relates to the Greek goddess Persephone, daughter of Demeter, the goddess of agriculture. Apparently Hades abducted Persephone into the underworld to be his wife, and Demeter threatened to shut down growth on the earth. Zeus—Persephone’s father, god of the sky—brokered a deal where Hades only spends a short time with Persephone each winter, so Demeter shuts us down just for a little while.)
In the high tunnels—greenhouse-type structures heated only by the sun—we are seeding kales; spinach; lettuce; Asian greens; fast-growing root crops, like turnips, radishes and carrots; celery; and fresh herbs. These are foods that can be harvested all winter, we hope.
And then there are old-fashioned, woven-cotton row covers that we place directly over plant rows to hold soil warmth like a blanket. We bend 1/2-inch electrical conduit, or #9 wire, to make arches and poke the ends into the ground to form low tunnels. We weight down the covers along the edges, otherwise they’ll be lost to the slightest breeze. This system is more vulnerable to wind, harder to harvest from and sure to collapse under heavy snows, but it protects the plants enough to keep the kale coming a little longer. In the winter, we have to wait for the plants to thaw before harvest, and sometimes the covers are frozen to the ground, but usually we can work around the forecast to get some harvested for orders in the online store and the year-round weekend farmers markets in Lexington and Hyde Park (Cincinnati).
Even though it feels like global warming is upon us, we are actively preparing and continually improving our various cold-weather plant-protection systems so we can all eat local, organic greens all year. Thank you for entrusting us with your food needs all year long. —Mac Stone