No garden can be successful without healthy soil. Often mistakenly undervalued, soil is the fundamental resource sustaining everything on earth. Plant life and the organisms that depend on plants could not survive without it. It is a living thing with many parts systematically working together. Soil provides the minerals, nutrients, biological elements, and the structure plants need to grow and thrive. But, don’t confuse soil with dirt. Dirt refers to bits of debris that are unclean or dusty. Dirt cannot support plants, whereas soil is teaming with beneficial life.
Soils start as stones that have been broken down again and again over millennia by wind and water. Those become particles of varying size (sand, silt, and clay). Among these particles is organic matter, decaying plants, animals, and microorganisms like bacteria and fungi. Soil has pore spaces that fill with air and water.
up to one hundred tiny soil insects,
What are the characteristics of quality soil?
As gardeners, managing soil can be just as important as
managing the plants that grow in it. Soil should do what we want it to do.
Whether you are growing a vegetable crop, ornamental shrubs, or a lush lawn,
paying attention to your soil’s composition and fertility is vital.
The characteristics of soil are unique. Ideally, soil should have lots of organic matter, the capacity to hold water and air, and the ability to release nutrients to plants. It also functions to anchor plants, insulate their roots, and resist erosion.
Soil in the home garden.
Photo Credit: Alyson Ricketts, Burlington County Master Gardener
Soil can be categorized by its texture; sand, silt, clay, or
loam. Sandy soil provides good drainage to plants as it lets water freely pass
through, although it does not hold many nutrients. Silt particles are smoother
and silkier than sand. Clay is smaller particles and holds on to water and
nutrients, but can be difficult for plants roots to move through. Loam soil
contains lots of organic matter and is a combination of sand, silt, and clay.
The composition of your soil depends on your location.
Although soils vary widely across the state, New Jersey has a designated state
soil found mostly in southern locations.
Called “Downer” soils, they are loamy, acidic, and made of coastal plain
sediments. These soils are good for growing agricultural crops and sustaining
many species of woodland trees.
How do you know what is in your soil?
Thinking about soil first is an important step. Knowing the
characteristics of your soil will determine your approach to planting and can
help you decide what to plant and where. Some soils are ideal for specific
plants and not for others. Getting your soil tested is the only way to know
what’s in there. You want to know if your soil has issues that need to be
corrected or if any amendments are needed.
Getting a soil test is environmentally friendly because you won’t be
adding any unnecessary fertilizers that have the potential to run off and
contaminate waterways. Soil tests can save money because you won’t be buying amendments
you don’t need.
Fall is a great time to have your soil tested so you can prepare before the growing season. The first step in getting your soil tested is to purchase a test kit from the Rutgers Cooperative Extension county office or follow the sampling instructions on the website. Make sure to follow the sampling instructions carefully. About two cups of sample soil is required from several holes, dug about 6 to 8 inches deep. Also, you will need to submit a soil questionnaire. Areas used for different types of plants should be tested separately. For example, perennial beds should be tested separately from the lawn and separately from the vegetable garden. The report will arrive in a few weeks from the time of submission by email or mail. For questions about your soil report contact the extension office.
Rutgers Soil
Testing Laboratory
https://njaes.rutgers.edu/soil-testing-lab/
The soil testing lab
provides testing and reports to help
New Jersey residents achieve their
agricultural and environmental goals.
Soil pH
Knowing your soil pH (how acidic or alkaline) is important
because plants can’t take up the nutrients they require if the pH is not within
the optimal range. If the soil pH is not correct for the plant, soil amendments
can be used to adjust the pH. The soil test report will indicate if limestone should
be used to raise the pH or a sulfur application is needed to lower pH. A pH of about 6.5 is optimum for most plants.
Some plants have special needs, however. Blueberries, for example, prefer to
grow in very acidic soil with a pH between 4.0 and 4.8.
Macronutrients and Micronutrients
Soil already has nutrients in it. A soil test will tell you
what nutrients and how much it contains. Macronutrients are required by plants
in larger amounts than micronutrients. Macronutrients are nitrogen (N),
phosphorus (P), and potassium (K). Micronutrients are calcium, manganese,
boron, zinc, and copper. Depending on the levels, composted organic matter or
specific fertilizers may be needed. If applying fertilizer, use the correct
type and amount. Always read the label and instructions.
How to Care for and Maintain Soil
Keeping your soil covered with mulch, compost or a cover
crop is an important step. This will help with erosion control and also add
nutrients as the cover decomposes. Covering soil will help minimize weeds, retain
moisture, and moderate the temperature. Try to avoid walking on soil and
instead stick to walkways. Compacted soil becomes a problem because roots,
water, and air cannot move through it. This is why tilling, which can compact
soil, should be done in moderation. Try to avoid disturbing soil as this can
bring weed seeds to the surface to germinate. Finally, use an Integrated Pest
Management strategy to avoid overuse of pesticides which can kill some of the
living organisms in the soil.
Additional Resources:
Rutgers Publications Fact Sheet 719: “Soil Fertility Test
Interpretation”
https://njaes.rutgers.edu/pubs/publication.php?pid=FS719
Rutgers Publications Fact Sheet 797: “Soil Testing for Home
Lawns and Gardens”
https://njaes.rutgers.edu/fs797/
Penn State Extension: “Soil Quality Information”
https://extension.psu.edu/soil-quality-information
Rutgers Publications Fact Sheet 1135: Soil Organic Matter
https://njaes.rutgers.edu/pubs/publication.php?pid=FS1135
New Jersey Agricultural Experiment Station: “How to Have
Your Soil Tested”
https://njaes.rutgers.edu/soil-testing-lab/how-to.php
Jersey Friendly Yards: “Step 2, Start With Healthy Soil”
https://www.jerseyyards.org/create-a-jersey-friendly-yard/8-steps/step-2-start-with-healthy-soil/
Soil Science Society of America: “Soils are Living”
https://www.soils.org/files/sssa/iys/july-soils-overview.pdf
USDA Natural Resources Conservation Service: “New Jersey
Soil”
https://www.nrcs.usda.gov/conservation-basics/conservation-by-state/new-jersey/new-jersey-soils
Soil Science Society of America: “Downer, New Jersey State
Soil”
https://www.soils4teachers.org/files/s4t/k12outreach/nj-state-soil-booklet.pdf
Michigan State University Extension: “Soil…it’s more than
dirt”
https://www.canr.msu.edu/news/soilits_more_than_dirt
Rutgers University Extension: “Digging Deeper: What’s Your
Soil Telling You?”
Video: https://www.youtube.com/watch?v=O0rNVblU_08
Brooklyn Botanic
Garden: “How Compost Builds the Soil”
https://www.bbg.org/article/how_compost_builds_the_soil#:~:text=Feed%20the%20soil%2C%20not%20the,Bin%20A%20homemade%20compost%20bin.
