Soil is more than just dirt; it affects all of the foods we eat. But why is this really a conversation about history and why are we talking about this at the National Museum of American History this summer?
The way Americans have treated dirt throughout American history has had wide-ranging results, both positive and negative, on our food systems and our environment. Changing technologies in agriculture have led to changes in food production and farming methods. And most importantly, these stories about dirt and the technologies that affect it are really stories about people and their lives and work. To collect even more of these important American stories, the Museum recently launched the Agricultural Innovation and Heritage Archive, a project that asks the public to help us preserve America's changing and innovating agricultural history.
To learn more about soils and what goes into them, we talked with Harriet Wegmeyer and Coach Mark Smallwood. Both are practitioners working in the fields of farming and research, and will be panelists at this week's Food in the Garden event.
What role does soil play in to the health of our people and our planet?
Mark Smallwood from Rodale Institute: For plants to be healthy, the soil they grow in must be healthy, too. Healthy soil may be defined simply as soil that allows plants to grow to their maximum productivity without disease, fertility or pest problems limiting production, and without a need for unusual supplements or support. Fertile soil, rich in organic matter and microbes, creates a more stable environment for plants.
Harriet Wegmeyer of Wegmeyer Farms and Nutrients for Life Foundation: Soil is the key to gardening and farming. Simply put, healthy soil = healthy food = healthy people... It is important that both gardeners and farmers use soil tests to determine what nutrients need to be added back to the soil and at what amount. We are strong believers in adding fertilizer by using the 4R method—right product at the right time, right rate, and right place.
How and why does the soil affect the plants that grow in it? How does that affect what we eat on our plates?
Harriet Wegmeyer: Soil is different in every part of the country. Some soils are rich in nutrients, some are sandy, some rocky and some nutrient deficient. For plant growth, the most important job of soil is to provide the nutrients that the plants need to grow. All plants need 17 essential nutrients, with nitrogen, phosphorus and potassium being the primary three for healthy growth. These nutrients are available in the soil and travel to the plants via the roots. Plants that are grown in soil that is lacking in nutrients will result in nutrient deficiency and lack in overall quality and health of the fruit or vegetable.
What is the most critical thing backyard gardeners should know about soil?
Mark Smallwood: Just as the statement "milk is milk" is patently not true, so is the idea that all compost is created equal... While piling plant material in a heap and waiting long enough might result in rotted organic matter, it would still be a far cry from the truly fertile whole-food nutrition on which plants will thrive.
Whether gardeners and farmers make compost themselves or get it from an outside source, there is a wide range of practices that can lead to the final compost product. What matters in the end, though, is whether it will help your plants flourish.
Harriet Wegmeyer: After you have taken a soil sample and realize that you need to make some changes, there are a few simple steps to follow. If your space is small enough, you can add compost to the garden to build up the organic matter. Some people have a compost pile of their own and others purchase the compost.
Building up the organic matter in your garden can take years, but is worth the effort. Other additions to your backyard garden plot can be in the form of lime to change the soil pH, and fertilizer to provide readily available nutrients.
What is a little-known fact about soil that no one knows but should?
Mark Smallwood: Fertile soil, rich in organic matter and microscopic life, acts like a sponge, holding on to more water during shortages and keeping it from running off during heavy rains. Rather than total crop failure in times of stress, organic plants can rely on the soil to provide a measure of balance. Organic farming can successfully produce food even during extreme weather conditions.
Harriet Wegmeyer: It takes 500 years to form an inch of soil on top of the ground. Soil is a precious natural resource that takes a long time to form, so we must be careful with it!
What about dirt inspires you? Why are you passionate about this topic?
Harriet Wegmeyer: Soil is fascinating to me! It is responsible for everything that we have. I look at it from a farmer's perspective. If I take care of the soil, it will take care of me. I am here using this wonderful natural resource to grow food for my family and my community. I want to pass my farm to my three young sons and to do this, I must take care of the land.
For more information about the effects of farming technology on our environment and on American history, check out our National Youth Summit on the topic.
Wegmeyer and Smallwood will be joined tonight by Maxine Levin, National Liaison to the National Cooperative Soil Survey, for a discussion on soil.
Tickets are still available next week's Food in the Garden event on Thursday, August 15th, which will celebrate Julia Child's 101st birthday. Food in the Garden is made possible through the generous support of DuPont Pioneer and The Julia Child Foundation for Gastronomy and the Culinary Arts. The programs are presented by the Museum’s American Food History Project and Smithsonian Gardens.
Susan Evans is the Program Director of the American Food History Project. Read more blogs on food history here. New Media Intern Hannah Ostroff also contributed to this blog post.