Week 6, CSA News

Soil is the Soul

The foundation Elmwood Stock Farm is built on is a soil called Maury Silt Loam. This is a type of soil that is considered fertile with good structural components. How well plants perform is based on the physical and chemical properties associated with each type of soil and the wildly complex biological  happenings among the microbial community in the soil, out of sight.

The Science of Soil Management

Looking at the soil, you would think there's not much to it. It's just a bunch of dirt, after all. But the science behind it all is impressive.

Structural components of the soil are classified by the combination of sand, silt and clay particles that make up dirt:

* Sand is like big boulders that have big gaps between them, allowing water and air to pass between them easily.

* Silt would be comparable to pebbles that fit between the boulders.

* Clay particles are tiny, flat structures that stick together and fill in remaining voids. Less clay in the soil means more voids that allow roots to penetrate more easily and air and water to reach them. The sub-soil tends to be more clayey in the Bluegrass Region, which can form impenetrable barriers to roots, air and water.

How well roots can spread throughout the soil directly impacts the plant's ability to be well anchored and reach the nutrients it needs for optimum growth. A good mixture is considered a healthy soil, which we are blessed with on Elmwood Stock Farm.

The chemical properties of soils are important and are directly related to the structural components. Reaching back to high-school chemistry, the particles have positively and negatively charged properties called cations and anions. Like magnets, a strong positive charge will hold a negatively charged anion in place. This is the action that holds available nutrients—like calcium, magnesium, sulphur, etc.—in the root zone. We monitor the Cation Exchange Capacity (CEC), which is an indicator of how well the battery is charged, revved up and running. Plant roots and their symbiotic mycorrhizal fungi mineralize these nutrients for plant growth, but only when the soil particle is willing to give them up. Our relatively high CEC numbers—determined by a laboratory test—demonstrate healthy exchange of nutrients.

The biological properties of a soil bring all this to life. There are tens of thousands of species of bacteria, fungi and microscopic “insects” that colonize the soil. The more diverse these colonies are, the more likely they are to foster good plant growth. This microscopic ecosystem is called the soil food web. The microbes and microscopic insects, along with earthworms and larger insects, align the structural components to form little havens—even structural houses—called aggregates. Within these aggregates are chambers that are beneficial in holding water  to feed the microbes and the plant roots that encounter them. As these microbes prosper, they release nutrients to feed the plants and re-charge the CEC.

We are partnering with researchers from the UK College of Agriculture to monitor the diversity and populations of the components of our soil food web. The preliminary data indicates that, with our crop- and livestock-rotation plan, we can harvest vegetables three years in eight while maintaining a vibrant soil food web. We have no need for off-farm fertility fixes to feed our plants. (Sometimes we feed the soil with rock dust to add minerals and trace elements, but not very often.)

The Art of Soil Management

That is the science, now for the art of soil management. From decades of sound farming practices, our soils are like Olympic decathletes. The sand, silt and clay particles have been managed by us, the plants, and the diverse array of microbes to be able to perform in all conditions. Too much rain, and they drain the excess away efficiently. (Good farmers know not to handle the soil when too wet, as it will destroy the structure, which is why sometimes your veggies are not always available when you expect them.) Too little rain, and they hang on to all the moisture they can. A little disruption from cultivation, and they easily reform their colonies.

We are quite proud of the soils we have built here at Elmwood Stock Farm. When put all together, these soils would be considered not just healthy, but rich. Thank you for appreciating the quality of the produce they produce.

In Your Share:

Asparagus

Bok Choy

Broccoli

Garlic Scapes

Kohlrabi

Lettuce

Spinach

Sugar Snap Peas

 

Recipes

Asian Braised Bok Choy, adapted from Carpé Season

As with any stir-fry dish, be sure to have all of your ingredients at the ready so you can cook quickly. You can add other vegetables (such as kohlrabi, asparagus and sugar snap peas) or meats to this stir fry, too.

1 large bok choy, ribs halved and cut into 2-inch pieces

2 T. canola or vegetable oil

2 tsp. ginger, finely minced

2 garlic scapes, minced

1/2 c. water

2 T. rice wine vinegar

1/4 c. soy sauce

1/4 c. loosely packed dark brown sugar

2 tsp. toasted sesame seeds

1 T. minced chives

1 T. chopped cilantro

Heat oil in a large, heavy-bottomed saucepan or Dutch oven over high heat until shimmering. Add halved bok choy, cut side down, working in batches to avoid crowding pan, and sear until slightly browned, about 1 minute. Use caution with the oil, as it may splatter. Remove bok choy to a large plate or sheet pan.

Lower heat to medium and add ginger and garlic, stirring constantly, until fragrant, about 30 seconds. Add water and vinegar and bring to a simmer, stirring and scraping bottom of pan with a wooden spatula or spoon to loosen any browned bits. After 1 minute, add soy sauce and brown sugar. Add bok choy back to pan and cook, uncovered, until bok choy leaves are wilted and stems are tender-crisp, 6 to 8 minutes. Remove bok choy to serving platter.

Continue to cook liquid in pan over medium heat until it reduces to a glaze, 6 to 8 minutes. It will continue to thicken a bit as it cools. Spoon glaze over bok choy, and garnish with sesame seeds, cilantro and chives. Serve with a hot, cooked grain, if desired. 

Kohlrabi Chips, from Martha Stewart

Very thinly sliced, unpeeled kohlrabi

Olive oil

Coarse salt

Toss kohlrabi with olive oil. Season with salt. Arrange in a single layer on a baking sheet lined with a nonstick mat or parchment paper. Bake at 250 degrees F, rotating sheet, until crisp and deep golden, 35 minutes to 1 hour depending on thickness of kohlrabi; transfer chips as they're done to a paper-towel-lined plate. Season with salt.

Green Pasta with Blue Cheese, adapted from Nigellissima

8 oz. trottole verde, fusilli or any curled pasta

salt for pasta water, to taste

4 oz. Gorgonzola or blue cheese, crumbled or chopped

4 c. spinach leaves (packed)

coarse-ground pepper

3 T. chopped shelled, unsalted pistachio nuts

Cook pasta in salted water until just al dente. Before draining, remove a cupful of pasta-cooking liquid. Turn off heat. Drain pasta, then add pasta back into the hot pan with 2 tablespoonful of the liquid, plus cheese and spinach, and add some black pepper. Put the lid on the pan and let stand for 2 minutes.

Remove the lid, turn the heat back on low, and stir the pasta, cheese and spinach together, along with as much of the cupful of cooking liquid as you need until the cheese is melted into a light sauce and the spinach is wilted.

Remove from heat, toss with about two-thirds of the chopped pistachios, and divide between 2 warmed bowls, sprinkling each bowl with the remaining nuts. Serve immediately.