Recommendations for silty soils: Enhance and enhance silt

Many of the ancient civilizations of our world were created along the banks of rivers. This is no accident as rivers offered strategic resources. The ancient Chinese built the Yellow River and the Sumerians along the Tigris and Euphrates, the Indus gave birth to the ancient Indian civilization and the name “India”, and the ancient Egyptians worshiped the Nile. These people thrived because of their access to abundant drinking water, abundant irrigation, efficient transportation, and fertile, muddy soil.

Rivers are exposed to cyclical floods, during which a layer of mineral-rich silt is deposited on their banks. The ancient Egyptians called this annual event the "gift of the Nile" and attributed it to the tears of the goddess Isis for her husband Osiris. Early human societies were agrarian and based on agriculture. The key to their success lay in their ability to grow enough plants along these river valleys to eat and process into other products such as papyrus. In many ways, humanity as we know it today was built on Schlick.

Soil is a valuable resource, and some say a garden is as much about tillage as it is about growing plants. Of course, you are not expected to feed the world from your home garden, but understanding what silt is and how to work with that type of soil can help with your production.

What is muddy ground?

Silty soil is fine-grained and can easily erode. Source: Wiremoons

Before we get into muddy ground, we need to start with what exactly ground is. There is a whole field of science that is concerned with the study of soil and is called pedology. Soil is a mixture of mineral particles, organic matter, organisms, gas and water. Scientists have advanced three types of soil textures – sand, silt, and clay – depending on the size of the solid mineral particles. Silt particles lie between sand and clay particles in terms of both size and physical properties. Soil texture determines how easily the soil can be worked, how it retains air and water, and how fast water can flow through it.

According to the USDA, silt particles must be between 0.002 and 0.05 mm, which makes them smaller than sand but larger than clay. These soil particles are deposited by wind, water or ice through the erosion of larger rocks. Dry silt feels like baby powder, and wet silt has a slippery and soapy texture. It does not clump up easily like wet clay or crumble like wet sand. In the United States, areas along the Mississippi and Missouri Rivers have the highest concentrations of silt. When the glaciers retreated from this region at the end of the last Ice Age, they deposited sediments on their way.

The soil texture is classified as silt soil if more than 80 percent of its composition consists of silt. According to this definition, pure silt is rare for the home garden. Your soil composition will most likely contain a mixture of silt, clay and sand particles, each with a different content. Many gardeners find loamy soil best for growing most of their flowers and vegetables. Loam is an equal mix of sand, silt and clay. This type of soil can hold moisture in during dry spells, but still has enough drainage for healthy roots.

How to improve silt soils

When planting containers or raised beds, there is less to worry about silt, sand, or clay when you buy or mix your growing media. However, when planting straight into the ground or filling beds with your home soil, you need to consider the soil particles and what you may need to add to improve your soil for plant growth.

First, prevent erosion

Clouding water from siltSilty soil can easily cloud waterways if disrupted. Source: NRCS Oregon

A productive garden starts with healthy and fertile soil. A key indicator of soil health is aggregate stability. Aggregates are clumps of soil made from a combination of clay, sand, silt and organic matter. This structure protects microorganisms, allows water to penetrate and retains moisture. Silty soils, which consist mainly of mineral particles with little organic matter, are usually unstable aggregates and experience erosion and compaction. While you may not be able to control factors like rainfall and temperature, you can make smart design and cultivation decisions to ensure a well-manicured soil environment.

If you have a sloping plot of land, there is a higher risk of your soil being washed away after heavy rainfall. Choose your garden spot carefully and try to find a level and dry area. If this is not possible, then you can try creating small terraces along the slope. You can build these terraces out of wood, brick, or stone. However, you need to make sure that the patios are well secured and have some drainage to avoid waterlogging.

Using cover crops or green manures is another way to prevent erosion. Cover crops act as physical barriers on the ground, protecting the soil particles from being carried away by the elements and anchoring the soil with their roots. Buckwheat and bersee clover are two cover crops that do well on muddy soils.

On the other hand, you can speed up erosion by tilling your soil frequently and physically breaking apart soil aggregates. Although this type of soil treatment is widely used in large-scale agriculture, it is better to work in the home garden with little tillage or no-till.

Work in a lot of organic material

Since pure silt is eroded mineral particles, it does not contain any organic matter. Silt in flooded rivers is mixed with all kinds of naturally occurring organic materials, which makes the sediment fertile. Your soil does not receive this natural change. For this reason, it is important to manually condition your soil type with organic materials to create more stable soil aggregates. Your goal is to achieve good soil quality with proper aeration, water filtration, and nutrition. The addition of soil microbes such as beneficial bacteria and fungi will also help your plants absorb nutrients more efficiently.

There are many sources of organic materials that you can use to condition the soil. For example, fallen leaves or garden waste are often free and abundant for the home gardener. You can also use regular vegetable compost, mushroom compost, or composted horse manure or cow manure as the organic material.

Changing your floor can take time. So be patient with the process. A good rule of thumb is to start with two inches of organic matter and work it into 6 inches of existing topsoil. Do not add your changes when the soil is wet to prevent accidentally compacting your soil.

Heavy mulching

Hay covered siltA mulch like hay can reduce erosion and add organics to the muddy soil. Source: preferably salt marshes

Similar to cover crops, mulch is also an effective way to protect your soil from erosion. In addition, mulch can help the soil retain more water by preventing excessive evaporation and moderate soil temperatures.

Many of the organic materials we discussed above can also make great mulch. Leaves or compost will continue to break down over time, adding more nutrients to the soil. Straw and wood chips can also be used as a nice layer of mulch. If you want to give your garden a better look, you can apply bark or composted bark mulch. Apply a generous layer of 3 to 6 inches of mulch for best results.

The best time to apply mulch is at the beginning of the growing season, after the soil is completely thawed. Applying mulch too early can slow seed germination and plant growth by keeping the soil too cold or too moist. If you're using mulch to insulate the soil and keep it warm in winter, use a thick layer of material like straw to make it less compact under snow and ice.

Fertilizing silt

Make sure you do a soil test for a basic understanding of your soil condition. This step is especially important if it's your first year of planting. Collect soil samples from several parts of your garden, mix the samples together, and send them to your local soil testing laboratory.

Using organics like manure and compost will help fertilize your soil, but the nutrients may not be immediately available to your plants. Calculate the square footage of your garden to determine how much additional fertilizer you will need and carefully follow the directions on the fertilizer packaging. More is not always better. You should stick to the recommended amount for your space. Excess chemical fertilizers can dissolve and enter the water drain, causing eutrophication of your local watershed.

Nitrogen (N), phosphorus (P) and potassium (K) are the main nutrients that plants need for healthy growth. However, different cultures can have different nutritional requirements. This is another important factor to consider. Fertilize at the beginning of each planting season and dress later in the year when you have heavy feeds.

How to water silt

Sludge flows from the handSludge is so fine that it can briefly float in the air. Source: stephmotogirl

The type of soil texture will determine how often you need to water your plants. Fine soils such as silt or clay particles have a larger surface area than sand, rock or gravel. As a result, silt and clay soils can hold back more water and have a high water holding capacity. You may need to water muddy soils less often than sandy soils, even if the total amount of water reported is the same.

Keep in mind that regardless of the soil texture, there are still many proven watering methods in place. Drip irrigation is a great way to water without waste. Try not to water or wet the leaves too much during the heat of the day. As always, use a mulch to help maintain soil moisture and prevent evaporation.

Good plants for silt soil types

Plants generally prefer muddy soil over clay or sandy oil. By adding organic materials, you should be able to grow many types of plants in your garden with the exception of root vegetables, which prefer loose and sandy soils.

Vegetables that grow well in clay soils thrive in muddy soils because both types of soil can retain moisture. Dry silt does not crack like clay and puts additional strain on the plants. Flat-root vegetables like lettuce, onion, broccoli, and other related brassicas are good options. Nitrogen-fixing vegetables like peas and legumes are also great for further improving your soil.

A lot with muddy soil would be well suited for a three-sister garden with corn, beans, and pumpkin. Corn is a shallow root vegetable and the corn stalks would act as a natural grid for the beans. The beans would add nitrogen to the soil and the pumpkin would provide ground cover. This type of companion planting was developed by Native Americans and these plants played a central role in their culinary traditions.

About the writer Huan Song:

Hello, my name is Huan.

My love of gardening was inevitable because I was raised by two epic green thumbs grandmothers. One was a paleobotanist who had all kinds of weird and cool seeds around the house, and the other was a farmer who turned into a dumpling entrepreneur and valued the freshest ingredients.

Studying environmental science and marketing in college, I was miraculously able to combine those interests into a career in nonprofits focused on social justice, food security, and sustainability. In one of those roles, I drove a big green pickup truck with fruits and vegetables to teach kids where their food comes from and how to eat healthier.

I currently work at a Big Ten science communication university and spend my free time gardening, making garden videos, and trying to keep my cat Nevis from destroying anything in sight.

The green fingers behind this article:
Lorin Nielsen
Lifelong gardener

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