Soil Basics for Flower Gardening


Soil is often divided into various categories, such as clay, sand, silt, and loam, although there are actually an infinite number of soil varieties because soil compositions can vary widely in organic matter, large and small rocks, minerals, pH, and other factors.

Most gardeners consider soil that has a combination of sand, silt, clay, and organic matter to be good soil. Measuring the pH of your soil is also a good indicator of how your flowers will perform and will help you determine if you need to make changes to the soil composition. Here is a terrific little electronic soil testing tool that can tell you how your soil is doing quickly and easily.

pH and Flower Gardening

pH is a scale used to measure the concentration of hydrogen ions in a solution. The pH scale ranges from 0 to 14. Acidic substances have smaller pH numbers and more hydrogen ions. Alkaline substances have larger pH numbers and fewer hydrogen ions. 0 is extremely acid; 7 is neutral; and 14 is extremely alkaline. Limestone is an example of a very alkaline mineral. Sulfur is an example of a very acidic mineral. Note that arid regions tend to have alkaline soils and regions with heavy rainfall tend to have acidic soils.

Although the pH scale only has a 0 to 14 range, it is a logarithmic scale that is designed to measure vast differences. Think of the Ritcher Scale of earthquake magnitude as another example of a logarithmic scale. For example, a pH of 7 is neutral, but a pH of 6 is ten times more acid than a neutral 7. A pH of 5 is a hundred times more acid than a neutral 7, and a pH of 4 is a thousand times more acid than a neutral 7. Likewise, a pH of 8 is ten times more alkaline than a neutral 7. A pH of 9 is a hundred times more alkaline than a neutral 7, and a pH of 10 is a thousand times more alkaline than a neutral 7.

Testing Your Soil pH

To test your soil, it is a good idea to dig out samples from several places to see what the soil is like. Soil that hasn’t been worked is seldom ready for new plantings. It may have too much clay, too much sand, tons of rocks, very little organic material, a high or low pH, or other issues that you’ll need to deal with before you plant.

A good way to test the texture of your soil is with the “Ribbon Test.” After you take a soil sample, roll it back and forth in your hand. If it sticks together easily, it is high in clay, if it simply falls apart, it is probably has a lot of sand. Clay soils don’t drain well and are difficult for the roots to penetrate. Sandy soils drain well but don’t retain nutrients. Adding organic material will help both sandy and clay soils

You can test the pH of your soil with a simple pH testing kit. A good quality pH test kit is worth the extra expense because inexpensive ones are often inaccurate. The most accurate way to test the overall health of your soil is with a Garden Soil Testing Kit. These kits are relatively inexpensive and come in various styles. You can even buy an electronic soil tester that will also test the pH, as well as fertility, how much light you are getting, and other aspects for effective flower gardening.

The Magic of Compost for Successful Flower Gardening

If your soil is extremely acid, which can happen in an area with heavy rainfall, or with soil that has had overdoses of chemical N-P-K fertilizer, you may need to add limestone to ‘sweeten’ the soil.

Adding compost can also work wonders if your soil is out of the ideal pH range. This technique will also improve soil that is too sandy, has too much clay, or is low in the organic material that plants need to thrive. If you don’t know much about composting, don’t worry. You can find more information on composting at the Compost Guide.

Soil drainage is also critical to flower gardening. Mixing in compost is the best way to improve drainage. You can also try digging out a good quantity of the soil, around 16 inches deep, and placing a layer of fine gravel at the bottom.

Mulch and Flower Gardening

If you don’t have humus available from well composted material, you can help your garden through mulching. Mulching is nature’s way of composting. Forests provide a good example of nature’s mulching and composting system.

Forests are a complex growing community. Everything in a forest is related and works together. Leaves and dead branches fall from trees and other forest plants. Bacteria, fungi, nematodes, earthworms, and other habitants of the soil help break down the leaves and other debris into humus.

Humus is a natural living environment that benefits tree and plant roots.
To reproduce the mulch that forests naturally create, you can use garden waste from your home, such as shredded leaves, hay, shredded bark, or other similar substance. By spreading the material over the top of your garden dirt, you are mimicking the decomposing leaves and branches that make up a forest floor.

Mulching helps to keep weeds from growing and facilitates moisture retention in the soil. Mulching also begins the process of natural composting. Between treatments, soil organisms help to decompose the mulch that is closest to the ground. Earthworms and other critters that live in the soil pull composted material into the ground and naturally feed your plant’s roots.

You should add a little more mulch each year to your flower garden to keep the process going. You can use mulch even when your soil is in excellent shape. The mulch will keep the soil healthy and productive. You can further support your soil by adding a dose of organic fertilizer. Your mulch will work best when you add this natural fertilizer over the entire garden bed so that the whole area will gradually become healthier.

You can also go here for more information on mulching.

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