First-season, firsthand, soil-health indicators
What well-fed, biologically active soil looks, feels and yields like.

By John and Aimee Good
Posted December 14, 2006


Photos by Mu-Yeong Park

“Wow. Even the tire tracks are soft!”

These were among the first words Aimee and I uttered when we came to check out 8 acres of cropland for lease at The Rodale Institute’s research farm near Kutztown, Pennsylvania. We were looking for a new place to operate our CSA and market farm operations. Like any good farmers considering a new piece of land, first on our agenda was to get out on the farm and take a walk around.

We were immediately struck by the health and resilience of soil that has been managed organically for 30 years. It was while walking the rows of soybeans that Aimee and I first noticed the springy, sponge-like feel to what should have been the most compacted part of the field, the tractor tire tracks between the rows.

We smiled at one another, realizing we were going to have the opportunity to work in some really nice ground.

We came to the Institute after four years of farming at the Charlestown Cooperative Farm CSA in Phoenixville, Pennsylvania. During our tenure there, we worked with the landowners to develop a model CSA on land that had been conventionally managed by a local custom farmer.

In our first season there, the CSA served 40 members on about 1.5 acres. By our fourth year, we were tilling 7 acres to supply a 150-member CSA, a thriving farmers’ market, and selling to a local restaurant. We started out our first season plowing down the hayfields on the land, while cover cropping the acreage that had been managed in a corn/soybean rotation. In our fourth and final season at Charlestown, we had every available piece of flat—or even somewhat flat—land in production.

We moved to the Rodale Institute for the 2006 season in order to start our own farm business and move closer to Emmaus, where we both grew up. We dove in headfirst, starting up a 130-member CSA. We leased the land as well as greenhouse space and barn space for vegetable packing and distribution from the Institute.

News on our knees

Our first season operating Quiet Creek Farm CSA was a challenging one, as all first seasons are, but we successfully got the farm up and running thanks in no small part to the excellent soil we have the privilege of farming.

We first had our hands and knees in the dirt in November 2005, when we planted our garlic seed at the new farm. We had the Rodale field operations crew till and mark four, 250-foot beds for garlic planting. We brought our seed garlic and trowels, ready for a long day planting in cold, wet, late-fall soil conditions.

Immediately we were struck by the fact that we were not working in tired, worn-out soil. This dirt was rich and soft, more like a garden than typical farm soil. We tossed our trowels and continued to plant several thousand garlic cloves in half a day, pressing the seed 4 inches deep using only our hands.

While we have always fertility tested our farm soil and done our best to balance nutrient levels accordingly, we also farm with the belief that in the end, biological activity is the best measure of soil fertility. Aimee and I studied environmental science in college, and have worked hard to apply our belief in the resilience and fortitude of healthy ecosystems to farming. At Rodale, we have first-hand experience in the long-term benefits of building a healthy soil ecosystem.

So what does biologically healthy soil look and function like, from a farmers’ point of view? As small-scale vegetable farmers, we have an intimacy with our soil born of long hours on hands and knees planting, harvesting and lots and lots of hand weeding. While we do most of our cultivation with tractors, we have not found a way to grow clean greens, alliums and carrots without getting our butts off the tractor and down to the soil’s plane.

The earthworm factor

Back to the garlic. In March we went to check out how the seedlings were emerging beneath the blanket of straw mulch we had put down in early winter. We pulled back the straw and saw that the plants were coming up nicely, and then noticed the soil surface was riddled with worm holes. We were excited; worms are, after all, the chisel plows of the subterranean biological community.

I’m not good on measurements and don’t recall the exact spatial density of those worm burrows. What I do recall is the sound of those earthworms. As we walked along the mulched rows, or even the grass roadway adjacent to them, we could actually hear the earthworms. More accurately, we could hear the slurping sound as they slickly retreated into their burrows as we approached.

I have heard the same sound from night crawlers skittishly submerging at night on a farm where Aimee and I apprenticed. At first we were unsure of the origin of the sound. Then we caught the shine of the slithering forms in our lanterns. The farm was laden with earthworms, and coincidentally had also been managed organically for 30 years.

That brings us to . . .

Tip Number 1: You know you have a biologically active soil when you can hear your earthworms.

In April we began setting out the onion transplants we had started in soil-filled benches in the greenhouse. We planted out around 6,000 onion, leek, and scallion transplants by hand, once again enjoying lots of quality time down at soil level. With every stab of the trowel we were greeted with more worms. Two or three worms emerged in a panic nearly every time we plunged the plants into the ground. This was a truly amazing worm density we had not expected. Our previous farm had a similar loamy soil and comparable nutrient and organic matter levels after amending, but we had nowhere near this level of biological density.

There is a downside to having an abundance of earthworms. We found that the small redworms in the soil also judged some of our crops to be excellent burrowing habitat. We sustained heavy damage to our hakurei turnips—and to a lesser degree to the fall rutabaga—from small worms tunneling through the skin. The damage was primarily aesthetic, but did render the turnips unmarketable even for our CSA customers. Perhaps the worm damage was due to this season’s drastically wet conditions, or maybe we have a little too much of a good thing here.

Give ’em shelter

One of the most important aspects of building biologically healthy soil is habitat creation. The key to being hospitable to earthworms and other macro- and micro-biotic creatures that help build soil is providing shelter and food. Our primary means of doing this is cover cropping.

The Rodale field crew seeded the ground we were going to farm in a rye and hairy vetch cover crop in November 2005. This was very late to get the cover crop established in our area, but to our surprise the stand establishment was excellent. One of the great benefits of having a living soil is the forgiveness factor.

We have found through direct comparison with our previous farm that cover crops establish better and are more vigorous in biologically active soil. When we first seeded the conventionally cropped acreage to cover crops at the Charlestown CSA, we found we had to seed at high rates to get good stands. We also discovered that in this tired, compacted dirt our cover crops grew poorly, rarely reaching more than a foot in height before going to seed in our first years there.

At Rodale this has not been the case. After last fall’s late seeding of rye and vetch, our over-wintering stand was less than 2 inches tall, and, to our eyes, not worth a nickel. Then came spring, and the cover crops went crazy. The rye grew to nearly 4-feet tall, and the vetch formed an impenetrable thicket. There is no walking through a mature stand of hairy vetch at the Rodale Institute, lest the hydra-like vines entrap you and you end up becoming food for the robust population of decomposers in the soil ecosystem.

That is . . .

Tip Number 2: When you are afraid of your hairy vetch, you know you have a biologically healthy soil.

After 30 years of organic management including heavy use of cover crops, the soils at the Institute have become prime habitat for the myriad organisms that make up a healthy, living soil. Through remembering our experience of rehabilitating tired dirt into living soil, we can attest to the benefits of good, long-term soil management.

Forgiveness factor fantastic

This brings us back to the forgiveness factor. Biologically active soil is easier to work and more resilient when conditions are less than ideal. The loose, crumbly structure of soil that has been well managed over a long period of time holds up better during drought and deluge. For market farmers doing a lot of work by hand, it’s easier on the old hands and knees.

At our previous farm, we had a lot of trouble with erosion in wet weather and hard crusty soil in dry periods. In prolonged dry spells, we were simply unable to dig our carrots with a fork. We wore out our feet and knees, even jumping on the digging fork, until we finally decided we had to wait to dig our carrots until it rained. And this was in a silt/loam soil!

The soil also developed a hard, platy crust in dry weather, baked to the consistency of concrete in the summer sun. As you can imagine, this was a chore to cultivate. The sweeps and tines on our tractor-mounted cultivators had to be set very aggressively to penetrate the soil crust, and once they did they threw clods and soil bricks onto the tender plants we were trying to clean up. Hand weeding was similarly frustrating. Not only was it nearly impossible to pull the roots of weeds out of the tight soil, but the hard crust did a number on your hands, knees and elbows. Imagine crawling for a couple of hours on road gravel and you will get the idea.

And then it would rain. In a good downpour our soil would make a break for the nearest low spot on its way down to the creek. We would get bad ruts cut by the rushing water-borne soil and sometimes even lose significant amounts of our crops. This was definitely not sustainable. As mentioned before, this was loamy soil with around 3-percent organic matter and good nutrient composition. The problem was the soil was devoid of life. It lacked any of the structure or aggregation that a healthy population of soil organisms will create.

This past spring our onions suffered through an unusual drought period in April and May, followed by incessant, heavy rain throughout late June and July. We were irrigating our alliums in April and wading through ankle-deep water to weed them in early summer. At times this summer, the rain would spawn creeks and ponds in the onion field, leaving it looking like a rice paddy.

At harvest times we brought in the nicest onions and leeks we have ever had. Our onions were consistently the size of baseballs, and the leeks were so tall we had to bend them to fit in our CSA boxes.

We had similar good fortune with other typically difficult-to-grow crops. Our spring and fall broccoli, often tough to grow here, was incredible. At the height of the harvest we gave our CSA members three to five broccoli heads a week. And these were big heads weighing in at around a pound each.

That brings us to . . .

Tip Number 3: When conditions are far less than ideal, and you are still reaping a good harvest, you know you have a biologically healthy soil.

The good news is that you do not have to have soil that has been managed organically for three decades to see results. We saw dramatic improvements at the Charlestown Farm in our four years there. In our final season we never had trouble digging carrots, and our cover crops were starting to approach the fearsome rye and vetch jungles we have encountered here.

The other good news of long-term organic management is that the results are cumulative. As you continue to create good habitat to foster a healthy soil ecosystem, the benefits grow exponentially. Improved soil gives you a better forest of cover crops, which creates fresh habitat for worms, beetles, bugs and other organisms. Each new layer of biological activity improves the soil so that it can stand up better to the elements and consistently yield healthy crops and heavy yields.

That’s the kind of soil that feels good and teaches young farmers well.