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How to Improve Your Soil's Structure, Feed Your Soil and Protect Your Soil

Soil quality

Clay soils are made up of microscopically small mineral particles. These tiny particles are flattened and fit closely together therefore the pore spaces between particles is very small.  The small pore spaces make it difficult for air and water to penetrate the soil.  Clay soils hold onto nutrients making them richer than sandy soils.

Sandy soil has comparatively larger particles that are rounded rather than flattened.  The particle shape and size allow for much larger pore spaces between the particles, therefore sandy soils contain a lot of air and drain well.  Because of the large pore spaces sandy soils drain quickly requiring more water and replacement of nutrients than clay soils.

Loam is a term used to describe soil that is somewhere between clay and sandy soil and that is well supplied in organic matter or humus.  It drains well, has good aeration and makes an ideal home for all the living microorganisms that break down organic matter and provide nutrients to the roots of the plants growing in the loam.

Remember clay soils are usually very fertile. Clay soils should not be worked when wet; it causes compaction of the soil.

Compost

Clay soil and sandy soil both 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 will help clay soil become more porous and sandy soils less porous.  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.  Let the winter rains do the work for you.

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 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 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 provide a source of nutrients to your plants.

 Feed your soil: Amendments, Compost, Worm Castings and Compost Tea:

1/4 Minus Fir  Amendment - A good amendment for potting mixes and for acid loving plants.

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 nuturient 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.

Vermi Green Compost - Green waste that has been composted with Actively Aerated Worm Tea and attention to moisture, temperature and air and allowed to finish.  It will life to you soil, especially bacteria and fungi which make up the foundation of the soil food web.

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 microorganism bring it into the soil. 

Premium Compost – A special blend of Vermi Green Compost, Diestel Structured Compost, Fine Redwood Amendment and Azomite Minerals.  Incorporate into your soil if it is compacted.   Mix with existing soil when planting.   Spread 1”-2” over the soil in the fall and early spring to provide minerals and nutrients as well as a good balance of microorganisms to the soil.   Available on request.

Redwood Amendment Ground up redwood, which is a byproduct of the lumber mills, has been stabilized with nitrogen instead of composted.  The Fine Redwood Compost has a rounded particle size good for incorporating into clay soil.  It helps aerate the soil making it easier for water to penetrate into the soil.  Over a long time the bacteria and the fungi in the soil will break the redwood amendment down.

Stable Bed Compost – Composted horse manure and stable bedding.   Spread it over the root zone of your plants in the fall.   Incorporate it into new vegetable and annual beds .

Balck Castings – 40 lb bags of Black castings from red 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.

Compost Tea Compost tea is a liquid concentrate containing all the beneficial microbial components that compost is famous for.  These living beneficial microbes are the biology that drives the soil food web in a healthy functioning soil.  The soil food web is responsible for:

  1. nutrient cycling - the break down and reuse of organic sources of plant nutrition, and their holding capacity in the soil;
  2. improved soil structure - through the formation of soil aggregates;
  3. increased porosity - resulting in better aeration and water retention;
  4. the degradation of soil pollutants and pH buffering.

Actively Aerated Compost Tea can be used a soil drench or a foliar spray.  For a soil drench use a least 10 gallons per 1,000 square feet.

Protect your soil: Mulch

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 BarkA 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 ChipsA 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.

Top Soil and Blended Soil Mixes

Essential Soil Landscape Mix - An engineered soil that is designed to resist compaction, good water penetration, good aeration, will support good root growth, has biological activator and a nutrient package.   Under most circumstances will not need additional organic fertilizer for one year.  Best used for raised beds and  landscape areas where you need 6” or more of soil.  Always mulch when done planting.

Nursery Mix – A blended soil mix made up of topsoil, garden compost, and redwood amendment.  Break up your existing soil and spread the Nursery Mix over the top.  Use an organic fertilizer

Potting Soil – A blended mix of fine redwood amendment, worm castings, coir, #2 plaster sand, garden compost, and horticulture grade red lava.

Rhododendron Mix A porous blend of fir bark, red lava and a little compost.  Good for use in pots or raised beds for Rhododendrons and Azaleas.  Can also be incorporated into garden beds to aerate and loosen clay soils.

Top Soil – sandy loam topsoil with very little organic matter.  Can be used for raising grades over 6” in the garden, building mounds and for raised beds.  If you use Top Soil in your raised bed you will need to amend it with compost, about 30% compost. 

Gardener and Bloome Bagged Products -  Potting Soil, Acid Potting Soil, Harvest Supreme, Soil Building Compost, Chicken Fertlizer

Natural Fertilizers:

Compost, mulch and natural fertilizers feed your soil by introducing and feeding the soil microbes.

Down to Earth Organic Fertilizers - All Purpose, Acid, Bio Turf, Bio Fish, Bat Guano, Alfalfa Meal, Cottonseed Meal, Fishbone Meal.

Doctor Earth -  All Purpose Fertilizer, Super Natural Lawn Food

Mycorrhizal Products - Soluble Root Growth Enhancer, Granular Root Growth Enhancer

Neptune’s Harvest Hydrolyzed Fish and Hydrolyzed Fish and Kelp – Feeds the biology in the soil.  Mix 1/8 cup per gallon of water.

Oyster Shell Lime - a good source of calcium, if a soil test says your soil needs additional calcium.

Rock Dust - Gaia Glacial Green Rock Dust adds trace minerals to your soil.

Feed your soil and your soil will feed your plants.