As a master gardener, I believe that having some basic knowledge of what your plants are growing in will help you to be a better gardener and have more success. Have you ever wondered why a plant grows great in one area, but that same variety dies in another area when it receives the same amount of sunlight and water? How do I know if the soil I am planting in is the one to plant?

To answer these questions, it helps to first know what soil is and its purpose. The soil is first and foremost the main source of nutrients and water for the plants in your garden. It provides a place for roots to grow to absorb nutrients, oxygen and water and to anchor the plant.

But what constitutes the soil? The soil is made up of approximately 50% minerals and organic matter in different stages of decomposition. The other 50% is air and water found in the space between the minerals and organic matter. It needs that space because it won’t grow much in compacted soil, as evidenced by the trail your dog leaves in the backyard. The air also helps in the decomposition of organic matter. The amount of minerals and organic matter varies from one soil to another. Dirt is soil that has no organic or mineral matter. Basically, it’s dead land.

The percentage of mineral and organic matter is affected by several factors, such as the types of plants grown, moisture content, drainage, and cultivation practices. Different plants will use different amounts and types of nutrients and water. That’s why crop rotation is recommended for vegetable gardens so that no particular crop depletes the same nutrients and gives the area time to recover. So where you plant tomatoes once, follow with cucumbers or something else the next, then go back to tomatoes after a few plantings.

Cultivating soils for long periods of time will generally result in the soil having lower levels of organic matter. Tilling the soil increases the amount of air in the soil, allowing organic matter to break down faster.

Well-drained soils tend to have a higher organic matter content because there is more oxygen and other nutrients that plants need, and therefore they break down organic matter faster. If your soil is poorly drained, there will be less organic matter present. Having your plants in soil that is supersaturated is just as bad as submerging it. When the soil has too much water, the plant cannot absorb oxygen and suffocates. Too little water and it withers and dies.

To test your soil for drainage, in moist soil, dig a hole 3 feet deep and 8 to 10 inches wide. Fill with water. If the hole is empty in 12 hours or less, it has good drainage, if it still holds water after 48 hours, it has poor drainage.

How can you tell what type of soil you have? Is it sand, clay, loam, or some combination? You can’t necessarily tell by the color. The color can be influenced by the colors of the materials that make up the soil, drainage, climate, temperature, types and amounts of minerals in the soil. A dark color that most of us perceive as good quality soil may be dark due to the color of the organic matter it contains, or it may be poorly drained.

Texture is another indicator of what type of soil you have. Is it sandy, clayey, sandy loam, or clay loam? In the field, the texture is determined by what is called the tape method. Gently rub or try to stretch moist to moist (unsaturated) soil between thumb and forefinger and try to form a ribbon. Notice how it feels and reacts when you touch it. The proportion of silt, sand, and clay determines the type of soil you have.

Sandy soil is quite familiar to most of us, it is coarse, feels rough or reminds you of the beach, and is not sticky. Sandy loam feels gritty, but also slightly sticky. But none of these should form a ribbon. Sandy soil is easily cultivated, drains quickly, holds a lot of air, and warms quickly. Great for growing things that grow in or on the ground, like potatoes and watermelons.

Clay sand has very little clay or silt and doesn’t hold together well when wet and you try to form a ball. Sandy loam feels gritty but has enough silt and clay to form a wet ball. The clay loam should form a very short ribbon of about 3 cm or less. The clay is very sticky, elastic and forms a ribbon of more than 3 cm.

Silty clay loam is soft when dry and becomes slippery or sticky when wet. It has more silt than clay. Clay loam is mainly clay. It is hard when dry and also becomes slippery or sticky when wet. The clay has 40% or more clay content. It is very hard when dry and difficult to break dry pieces with your fingers. It’s not very good for plants, but it makes great pottery. Loam contains equal parts of clay, sand, and silt.

It is good to know the depth if you intend to plant trees because the deeper the soil, the better chance the tree will have because the soil will hold enough water, nutrients and give the tree more support for its root system.

To find out how deep your soil is, try digging a hole as deep as you can to see where you hit a barrier. The barrier can be made of rocks, gravel, heavy clay, or something similar to cement. The deeper you can go, the better. Shallow soil slopes down 10″ or less, moderately shallow 10″ – 20″, moderately deep 20″ – 39″, deep 39″ – 59″, and very deep is 59″ or more. Fruit trees should have a soil depth of a few feet in order to grow well.

Some experts suggest doing a soil test either through a service like a local county extension office or a kit you get at a garden center. Go ahead and make one if you feel it’s necessary, but keep in mind that these aren’t very accurate; even those made in a laboratory. They also don’t check all the nutrients you might want to know about. Knowing what type of soil, depth, and drainage should get you off to a good start.

Ways you can improve your soil to add nutrients or improve drainage is to add things like shale, vermiculite, or perlite to increase water-holding capacity, but that can be expensive. Organic matter is best and you can add it in the form of compost, humus, or composted manure. It even beats poop. Or try growing a cover crop, such as grasses or legumes, by mulching or adding macro or microorganisms.

The easiest thing is to choose plants that adapt well to the soil you have. Look at which plants are native to your area and which ones work in your landscape. Some plants do very well with what we would consider worthless soil and some plants like wet feet. Then it’s a matter of doing your homework and knowing what you have and knowing what to plant where.

There is a lot to learn about soil that will help you better understand your garden and I believe that if you understand the “why” it will make it easier to find solutions to your garden problems and make gardening more enjoyable.