soil blocks

Soil Blocking, or Making Soil Brownies

Students always call them soil brownies, and they do look tasty!

Soil blocking, which was developed in Europe and largely popularized in the US by legendary organic farmer, Elliot Coleman, is a practice of starting seedlings in cubes of compressed soil. While Rural Studio Farm still makes use of plastic flats for starting seeds of certain crops, soil blocks eliminate the waste and expense of using plastic containers.

The blocks are made in metal molds from a mixture of soil made here on site at Rural Studio Farm, which makes them more labor-intensive to begin with—and thus might not be suitable for larger scale farms.

However, farm manager Eric has found that, overall, seeds tend to germinate and grow better in blocks, and transplanting soil blocks into the field is faster and easier than having to remove each individual seedling from its tray.

Throughout the past two weeks, tomatoes, eggplants, and peppers that were started in 2-inch soil blocks were upgraded to 4-inch blocks to allow the roots to continue to develop before being transplanted to the field once the soil has warmed up more. The 4-inch mold is made with a 2-inch cavity to accommodate such an upgrade.

There are other advantages to soil blocks. As the growing roots reach the edge of a block, they stop growing in what is called “air pruning,” as opposed to wrapping themselves about as they would in a conventional pot or cell. Indeed, as the blocks are transplanted directly into the ground, root disturbance is almost entirely eliminated, meaning that more delicate plants that cannot tolerate root disturbance can be started this way.

Crop Cycles

This week was marked with large harvests, which were the endings of some spring crop cycles, and seed starting in the seed house, the beginning of new crop cycles.

A close-up of harvested and washed carrots, both purple and orange

Thankfully, teaching faculty, Mary English, Steve Long, Emily McGlohn, and Xavier Vendrell all graciously volunteered their time to help farm manager Eric during this busy period.

Harvested spring crops included lettuces, carrots, collard greens, kale, cutting celery, turnips, arugula, beets, and scallions, as well as herbs like spearmint, dill, thyme, and oregano. Many of these commodities were eaten fresh, but the rest were given to the kitchen where chef Cat processed and stored large quantities for future meals once students have returned.

At the same time, Eric and Emily started seeds for late spring and summer. These future crops were zucchini and summer squash, determinate tomatoes for the field, eggplants, red and orange bell peppers, spicy peppers, and butternut squash.

Eric also planted seeds for various beneficial insect-attracting flowering plants, culinary and medicinal herbs, and perennial ornamentals. While many of these accessory plants do not yield tangible crops, they do confer other benefits on the farm, such as bringing pollinators, deterring pest insects, and aesthetic compensation. It is also a key feature of Rural Studio Farm to use a polyculture model, planting a wide diversity of different crops and flowering plants.