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Nourishing Your Soil

Soil

Earthworms in soil

Soil is not all the same. Many people see dirt and assume it is homogenous, uniform, and perfectly capable of supporting their plants. Or sometimes people think if you plant plants in dirt and give them the right fertilizer then they will flourish. But take a step back and think about where the people who farm for a living grow things. Farmers have identified where the best soils are and are most successful growing in those places.

  • The Mississippi flood plains are fertile because the great river deposits nutrients when it floods.
  • The Great Plains were once vast prairies with grasses growing in continuous cycles for millions of years.
  • The Central Valley of California often turned into an inland sea and marsh during floods and after millions of years, the soil is some of the most productive agricultural land in the world.

Soil is a precious thing and is far from uniform, but thanks to thousands of years of human experimentation we know how to improve our agricultural soils as a rate far faster than Mother Nature.

Cover Crops

We can talk about each of our live’s purpose around a campfire sometime, but you can think of a plant’s life goal as collecting enough sunlight in-order to reproduce. Plants accomplish this by building up a root system to find nutrients and water, and leaves to collect Carbon Dioxide and utilize the sun’s energy for photosynthesis. Cover crops are any plant that we grow on the land that we do not remove. It is a crop grown specifically to return to the soil and take advantage of all this energy and plant structure that a plant gathered in its life. By releasing this energy back into the soil we stimulate the microbiology of the soil and actively create a more fertile soil for our main crop plants. Cover crops also improve the moisture-holding capacity and aeration of our soils. So when it rains hard the soils counterintuitively hold more moisture without being waterlogged while remaining aerated. These are just a few benefits of growing cover crops and working them into your yearly garden plan has huge rewards.

Compost

Compost is just organic matter(plants) that has decomposed and is often full of the bacteria and fungus that grew to decompose the material. Compost can be a quick way to add organic matter and soil biology to your soil, but is entirely dependent on the compost you purchase and shouldn’t be viewed as a long-term solution. Many composts are made from municipal leaves/lawn clippings/wood and are often improperly composted leading to burnt and partially composted wood that do more harm than good in your garden. Compost should be rich smelling, moist, and not have any solid wood pieces in it. If you can’t find compost you like, consider making your own. Microbes do all the work and you just have to help! I also encourage you to have a plan and ask yourself some of these questions before you go and spend your hard-earned money on compost.

  • Are you trying to bring in nutrients? – Compost have very little nutritional value and if it has wood pieces, it will actually hold nitrogen from your soil away from your plants
  • Are you trying to bring in organic matter? – For a small space this can be an excellent option. However, a cover crop is a far superior option for larger gardens
  • Are you trying to increase your microbial activity in your soil? – Why isn’t the microbial activity in your soil already high? Is there anything you can do to change that before adding compost?

Soil pH and Limestone

North Carolina has some of the oldest soils in the world and they have been rained on for millennia. This combination has weathered our soils and led to naturally acidic soil. This is great news for acidic-loving native plants, but less so for most of our fruits and veggies than have been bred in more neutral pH soil. Limestone is a mined rock you can add to your soil that neutralizes acidity and will help your plant roots better find and take up nutrients.

More information all about Soil pH

Variety Selection For Your Location

You may have noticed that plants growing in the wild tend to occur in patterns. You wouldn’t expect to see a cattail growing in the middle of a dry pine forest or a cactus growing in a jungle. Plants naturally have found “ecological niches” or what I like to think of as their favorite place to be through thousands of years of trial and error. When we plant vegetables they are no different than native plants and different varieties of plants tend to grow better in different soils and climates. Purchasing seed you neighbor has been saving year-after-year means the plants have been slowly figuring out how to grow here and passing that information along in their genes. If you have no idea what varieties to plant, purchase as many varieties as possible and start your own scientific experiment. With each season you can hone your knowledge and improve your skills!

Check out the Caswell County Veggie Guide for help in selecting varieties and a whole lot more!