Posts Tagged ‘soil’
…“What’s in your soil?
In fact, half of the ideal loam consists of elements we don’t consider to be soil at all: water (25%) and air (25%). But the solid components determine how much air and water the soil can hold. Organic matter — humus (decaying plants) and soil organisms — may only account for about 5% of your garden soil. The balance is mineral particles of varying size, including sand (largest), silt (finer), and clay (finest). The more sand, the more air the soil will hold, but water will drain away too quickly if sand content is too high. Silt and clay hold water more effectively, but too much and there may be no room for the air which is essential for root respiration and nutrient exchange.
And so, when we asses soil for gardening, we’re looking for an ideal balance of elements.
When sand, silt, clay, and humus are each present in roughly equivalent quantities, you have a good loam to bring a smile to any gardener’s face. Once you discover what’s in a spade-full of your own dirt, you can choose to add various amendments to make conditions more hospitable for your garden’s intended occupants. Or to take another approach, you can choose your plantings based on your soil. Perennials and fruit trees like sandier (though still moist) soil, while many vegetables such as melons, squash, and brassicas including broccoli, cabbage, and brussels sprouts will do well in denser, wetter soil. Talk to other local gardeners who may have similar soil.
How to get a good soil sample
Choose a representative spot in a garden bed or planned planting site. You may wish to test a few different areas, as results can vary even within a small area. Remove any plants and debris from the surface. Use a shovel to remove a chunk of soil about 6-8 inches deep and set it aside. Now you are ready to scoop your testing material into a container. Insert your trowel vertically along the edges of the hole to obtain a cross-section of topsoil. This is the crucial layer for most garden plants, especially annuals. Mix up the resulting strips of soil until you have a fairly uniform substance.
Use your senses
Rub some dirt between your fingers and take a close look. Is it gritty, crumbly, sticky, fluffy, silky? You will begin to understand the texture and composition of your garden just by looking and touching. Next, bring a handful near your face and take a deep breath. How does it smell? If your soil is fertile with an abundance of healthy microorganisms, it will smell pleasant and “earthy”. Any offensive odor indicates your soil is putrefying with anaerobic bacteria and needs aerating — just like tender roots, the “good” bacteria need oxygen to thrive.
Test 1: Soil Composition
Trowel four inches of soil into a quart-sized glass mason jar. Fill the jar with water up to the neck, tightly screw on the lid, and shake vigorously. Now set the jar aside for at least 24 hours. When you return the next day, the sample will have settled into visible layers showing the proportions of your soil components. Sand goes quickly to the bottom, with silt just above, then clay, then organic matter. Bits of undecomposed plant matter will float on top. If the water is still opaque with dissolved clay, try leaving the jar in a dark place (to prevent algae growth) for a few more days. Measure each layer.
“Cover crops just might be the hardest-working plants you’ll ever grow. Cover crops (also called green manure) suppress weeds, build productive soil, and help control pests and diseases. Plus, cover crops are easy to plant and require only basic care to thrive. And they grow well in nearly every part of the country. Get started! Maybe you already know about the benefits of cover crops but think they’re just for farmers and other large-scale growers. Think again. Cover crops are well suited to all gardens, whether they’re big or small. Here’s a step-by-step guide to reaping the rewards of cover crops in your garden…”
“If you have any interest in gardening or farming, there is another player in addition to the plants and soil that you should know about: mycorrhizal fungi. This type of fungus forms a symbiotic relationship with approximately 90% of plants! The fungi colonize the roots of the plant and then extend their hyphae far into the soil, bringing nutrients and water that would otherwise be out of reach to its host. In return, the plant provides the fungus with carbohydrates.
There are two types of mycorrhizal fungi. Shown in the picture below, endomycorrhizal fungi associate with many agricultural crops and ectomycorrhizal fungi mostly associate with trees. Endomycorrhizal fungi penetrate the plant roots cells, while ectomycorrhizal form a layer around the root. Ectomycorrhizal are classified by producing mushrooms above ground, which endomycorrhizal do not do. Some popular edible mushrooms, such as chanterelles and truffles, are ectomycorrhizal. The entire underground structure of the fungus is called the hyphal network….”
Hugelkultur is raised garden beds that reduce or eliminate the need for irrigation and fertilizer.
Rivenrock Gardens writes…
“The further you enter into it; the deeper it becomes”, Dante
Imagine if you will, having been shrunk down to a microscopic size. You are now smaller than an ameba, but larger than a bacterium. You live in the ground, in a microscopic world of one celled and larger creatures. Some of them are living in the thin film of moisture around the soil particles. As you roam around, knee deep in the water layer around a large grainy sand particle, you see in the water film a multitude of animals and algae floating around in the tiny currents in this small world of water. Some of these small microscopic creatures are animals, catching the algae and bacteria and eating them. Some of the bacteria are dining on algae, and also the dead bodies of the animals that live in this film of water clinging by static action to the sand grain.
You however are large enough to leave this film of water and venture to another particle nearby. This one is up against the sand grain; it is a particle of compost. This particular piece is so decomposed that it is not possible to distinguish what it once was. But now it is a piece of humus, decomposed plant or animal matter. It is a fluffy segment larger than the sand particle. As you get closer to it you see that is so open and porous, its many cavities and cracks are full of tiny organisms. Some are the same as were around the sand, and some are different. This piece also has water in and around it, but since it is so porous it has soaked up water in mush the same way a sponge would. Its’ many cracks and fissures are full of water, in fact this piece of detritus is carrying more water than its’ own weight. And in all this water and organic matter there is a veritable colony of organisms at work, digesting the organic compounds of the compost, as they work at it their own waste products are released into the water in the particle. These compounds are worked upon in turn by even smaller creatures, and some substances from them form acids that help to etch the soil particles and hasten the breakdown of the material…”