Understanding Soil Texture: Sand, Silt and Clay
Your soil’s texture is determined by the percentage of sand, silt, and clay it contains. This is the mineral component of your soil. Let’s go over the qualities of sand, silt and clay.
How to Improve Soil Quality Through Nourishment and Protection
Qualities of Sand, Silt and Clay
Sand
Sandy feels gritty and you can see the individual particles of sand. The sand particles are more round in form. The particle shape and size create pore spaces that allow water to drain quickly through the soil and air to move into the soil. Sandy soils drain quickly requiring more frequent watering.
Silt
Silt is finer than sand, it feels slippery and looks like dust. Silty soils will drain slower than sandy soils and will not dry out as fast. Silty soils may develop a crust on top if they are not mulched. Silty soil can become compacted so protect them from foot traffic.
Clay Soils
Clay is very fine, and you cannot see the individual particles. The clay particles are flat like a plate and can stick together making it very difficult for water to move into the soil. Clay particles are so small that they have a charge and are able to hold onto some nutrients, making them more fertile. Clay compacts very easily and should never be worked with wet.
Soil Texture
Soil texture is a combination of these sand, silt, and clay particles. Regardless of your soil’s texture you can improve your soil structure over time, this is because soil structure is built by the microbial community. Learning how to support the microbial community in the soil will make all the difference for the plants in your garden.
How to Support the Development of Soil Structure with Compost
All soil can benefit from the incorporation of compost. Good quality compost will feed your soil, which in turn will feed your plants. Compost is rich in microbial life, which transforms the nutrients and minerals from the compost and your soil into a form that plant roots can readily utilize. Adding compost to a sandy or clay soil significantly improves the soil structure, which in turn makes plants healthier.
Compost is the great equalizer; a 2-inch layer of compost incorporated into the top 6 to 8 inches of soil as a one time application will help clay soil become more porous and sandy soils less porous. Future applications can be layered on the soil surface so the improved soil structure is not damaged. One cubic yard will cover 150 square feet at a 2-inch depth. A 1″- 2″ layer of compost over your garden in the fall is an easy way to feed your soil, depending upon your plants needs. Always cover compost with mulch to protect it from the elements so it can break down slowly into the soil.
Recommended Composts for Improving Soil Quality
Diestel Structured Compost
Made by the family that raises Diestel Turkeys. We know where everything comes from that goes into this excellent compost. The Diestel family takes great care with their compost, it is completely finished and has excellent fungal, bacterial, and protozoa numbers so nutrient cycling will start quickly. Great for vegetable gardens. For first time veggie beds spread 2″ over the top of the soil and incorporate into the soil 6-8″ or spread 1/4″ around the root zone of you plants. Great to apply in the fall over the top of your garden beds, cover with a 1-2″ layer of mulch.
Garden Compost
Green waste ground up cuttings from local plants and trees that are composted at high temperatures. Incorporate it into your soil or spread over the top of you soil in fall and let the microorganisms bring it into the soil.
Seacoast Compost
SeaCoast Compost is a premium, Biodynamic® compost crafted from the finest combination of sea and land ingredients. Gathers the “waste” from three iconic Oregon coast industries and use these high-quality inputs to create nutrient-rich compost. The mixture includes fish, shrimp and crab leftovers from seafood processing, alder hardwood from the lumber industry, and cow manure and bedding from organic dairies. They add homeopathic preparations to enliven the compost and stimulate plants to maximize their effectiveness in their environments. The resulting compost offers a feast for your soil and plants. Also a great compost for making compost extract.
Bu’s Biodynamic Compost
A Demeter(R) USA certified Biodynamic® compost. Contains no GMOs, pesticides, sewage sludge, growth hormones or synthetic chemicals. Excellent compost to feed your soil. Bu’s recommendation for poor soil: Break up the soil and apply up to 2″ of Bu’s Blend on top. Water deeply & repeat every 2 weeks or so until soil improves. The water will draw beneficial microbes deep into the soil, where they will work to improve soil structure and vitality.
Feed Your Soil: Organic Amendment Options
Improving your soil’s quality is key to growing a flourishing garden. Both amendments and compost play vital roles in boosting soil fertility, structure, and overall plant nourishment.
Soil amendments are materials added to improve the physical or chemical properties of the soil. They help adjust soil pH, retain moisture, and improve aeration. Common options include organic matter like worm castings, woody amendments, and specialized fertilizer blends.
Recommended Amendments for Improving Soil Quality
Organic Amendment Mix
This mix is generally used for improving most soils in water retention and aeration. Organic Amendment Mix helps to open up clay for water to be held and to be moved through the soil. Excellent for new sod installations, seeding, and for generic all-purpose soil amending.
Veggie Amendment Mix
Vegetable Amendment Mix is especially made for topping off existing vegetable beds. If your soil level in your garden bed has dropped over the seasons, top it off with 1″ of Vegetable Amendment Mix in the Fall and Spring.
1/4 Minus Fir Amendment
A good amendment for potting mixes and for acid loving plants.
Redwood Sawdust
A byproduct of the lumber mills, sawdust from redwoods. Provides carbon matter to break up clay soils. It helps aerate the soil making it easier for water to penetrate into the soil.
Ligna Peat
Ligna Peat is 100% pure, organic, and sustainably harvest redwood fiber. A sustainable and local alternative to Peat Moss. Ligna Peat provides beneficial organic matter for a sustained period of time without rapid decomposition. Commonly used for aeration and water retention within the soil.
Worm Castings
Worm castings from worms that have been fed an organic diet. Worm castings are high in beneficial organisms and will inoculate and improve the quality of your soil. Use up to 10% in potting mixes or planting holes. Spread a thin layer around the drip zone of your plants and mulch over the top.
Down to Earth Organic Fertilizers
Down to Earth offers a lot of formulations, be careful to select a fertilizer that is correct for your individual plant needs.
Mycorrhizal Products
Granular Mycorrhizae products can provide an immediate boost to your microbial community by working directly with your plant’s roots to increase their nutrient uptake. Improves root growth and expansion which in turn improves soil quality. These are best applied when transplanting and are added to the bottom of your planting holes. – Granular Root Zone, Big Foot Mycorrhizae Granular
Oyster Shell Lime
A good source of calcium, if a soil test says your soil needs additional calcium. Follow lab instructions on application rates, can change the pH of your soil.
Rock Dust
Adds trace minerals to your soil. – Cascade Minerals, Azomite
Utilizing Liquid Soil Amendments
Compost Extract:
This easy extract can be made at home and provides both microbial life and soluble nutrients, all by steeping high-quality finished compost in clean water. Water finished compost extract around the root zones of plants, very beneficial for potted plants and even bare soil.
A good recipe is to fill a paint strainer bag with 4 cups of compost in a 5 gallon bucket with 3 gallons of water. Submerge the compost tea bag and gently massage it to help promote the release of beneficial microorganisms into the water. After 60 seconds the water should have a nice “Tea” brown color, now you may remove the teabag and strain any extra particles from the extract, then use it to water with immediately.
Soluble Mycorrhizae:
Performs like the granular forms listed above. It is water soluble, so can be used as an effective soil drench on established plants without disturbing the soil and existing root structure. – Soluble Root Zone, Big Foot Mycorrhizae Concentrate
Hydrolyzed Fish and Kelp Options:
Most often fish or kelp based, these rich liquids fertilize gently while feeding the biology in the soil. – Down to Earth Fish and Kelp, Fish On Hydrolyzed Liquid, Kelp Help Liquid Concentrate
Protecting and Improving Your Soil with Mulch
The term mulch refers to a material that is placed on the surface of the soil. In addition to dressing up the soil, mulch also performs some very beneficial services for the soil and the plants. Mulch will protect the soil from the sun, wind, and rain.
Mulch also helps the soil to retain moisture and helps prevent compaction. A 2-3″ layer of mulch will help keep plant roots cool in the summer. A thick layer of mulch also really does a good job preventing weed growth. Weeds that do come up can often be easily pulled. Mulch helps rainwater penetrate into the soil instead of running off. Over time the microorganisms in the soil will break down the mulch and it will provide a source of nutrients to your plants.
Mulch Options for Protecting Your Soil
Premium Arbor Mulch
Chipped wood from urban forest trees. A good mulch for all plants. Good for weed suppression when spread 2″ deep.
Mini Mulch Fir Bark
A fir bark up to 3/8”. Good mulch for acid loving plants. Good for weed suppression when spread 2″ deep. Some growers of California natives particularly like this mulch.
Small Fir Bark
½” to 1” chunks of bark, good mulch for acid loving plants. Good for weed suppression when spread 2″ deep.
Wood Chips
A chipped redwood that is inexpensive and long-lived, good for around plants and for pathways, prevents tracking of mud. Good for weed suppression when spread 2″ deep.
Ground Redwood Bark
A fibrous material, pleasant color. Some growers of California natives particularly like this mulch. Not an effective bark for weed suppression.
Feed Your Soil and Your Soil Will Feed Your Plants
Healthy soil is the cornerstone of a vibrant garden. By focusing on feeding the microbial life in your soil and by protecting your soil soil structure is built. Soil microbes cycle nutrients to plants, leading to stronger, more resilient plants. Good soil structure means good water infiltration, water is held within the small pores in the soil and available to the microbial community and plants over time.
At Lyngso, we provide an extensive selection of soils, organic composts and natural fertilizers to help you improve and maintain soil quality. Visit our display garden and landscaping yard in San Carlos for expert advice and inspiration and contact us today to learn about delivery options for your SF Bay area home.
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