What makes rich soil

Unfortunately, many soils do not have adequate levels of all the necessary plant nutrients, or conditions in the soil are unfavorable for plant uptake of certain nutrients. Soil scientists that focus on soil fertility are interested in managing nutrients to improve crop production. They focus on using commercial fertilizers, manures, waste products, and composts to add nutrients and organic matter to the soil. Sometime they also add chemicals that change the pH to a more optimum level for nutrient availability to plants.

Soil fertility experts must also be careful to ensure that practices are environmentally sustainable. Inappropriate management of nutrients can lead to contamination of lakes, rivers, streams, and groundwater. In addition, adding amendments to the soil is expensive and cuts into the profitability of farming operations, not to mention that toxic levels of nutrients can be as bad as or worse than too little nutrients for the plants.

There are 17 essential plant nutrients, three come from air and water carbon, oxygen, and hydrogen and 14 come from the soil. The table below describes the essential and beneficial elements obtained from the soil. Macronutrients are needed in high quantity, micronutrients are needed in small amounts, and beneficial elements are essential or beneficial to some plants, but not all.

Absorbed Form. Protein and enzyme component. General yellowing of leaves, stunted growth, often older leaves affected first.

Membranes, energy, DNA. Difficult to visualize until severe. Dwarfed or stunted plants. Older leaves turn dark green or reddish-purple. Osmotic balance. Older leaves may wilt or look burned. Adding peat moss helps make alkaline soil below 6. With a raised bed, you can maintain near perfect organic soil and planting conditions, kiss drainage issues good-bye, and tend to plants with less stress on your body. So how should you go about filling a raised bed with the loose, rich, organic garden soil that plants love?

Another option: Build the soil yourself, customizing the mix to suit whichever crop s you plan to grow. Some organic gardeners use 50 percent topsoil, 30 percent high-quality organic compost, and 20 percent organic materials, such as shredded leaves, mineralized soil check with a landscaping supply company , worm casings, ground bark, wood-based fire ash, and completely composted cow or chicken manure.

Top dress the surface with 1 to 2 inches of compost, then a couple of inches of mulch. Amend your soil at least once a year with organic nutrients to make up for what the plants take out. If you plan to make wholesale changes to a large garden plot, your best bet is to sow a cover crop to revive soils with limited organic matter.

A cover crop is a quick-growing annual, such as buckwheat, clover, rye, or barley, that is turned over or plowed back into the soil before it matures. It's also called green manure because plants are turned over when they're still green and immature; that's when they're highest in nitrogen.

Keep in mind that cover crops are relatively low-maintenance, but they still need to be watered during times of drought. Try this cover crop rotation to improve poor soil in a vegetable garden. Sow a thick crop of buckwheat a warm-season cover crop in the spring or summer, then turn it over when it reaches inches tall. Wait two weeks and sow another crop of buckwheat, again plowing it under when it's inches tall. Let the ground lay fallow left unsown to increase fertility until midfall, then finish by sowing winter rye.

Plow that crop under in spring. Then wait two to three weeks before planting vegetables because decomposing plant matter ties up valuable nitrogen. Start by excavating a row at the end of a garden bed. If you have to remove sod, set it aside for now.

Dig about a foot deep, saving the excavated soil on a tarp. Loosen the newly revealed hardpan at the bottom of the hole by sticking a spading fork deeply into it and twisting it around. Don't turn the soil over. Add an inch of compost, then refill the trench with soil you remove from the next row. Continue excavating row after row until you reach the end of the bed. Use the soil you placed on the tarp to fill the last trench. If good soil could be achieved merely by buying a bag of fertilizer from the garden center, most Americans would be boasting perfect soil.

While fertility is obviously an aspect of good garden soil, there is so much more involved. Good soil has:. The next thing to consider is the structure of the soil. There are three main types of soil:.

There are several things you can do to improve your soil. Luckily, they are actually all fairly easy to do. Test your soil: The first thing to do is learn all you can about your soil. You may want to try a couple of DIY soil tests to learn more about the level of life in your soil and what its texture is like.

Getting a soil test from your county's cooperative extension would be a great idea; this will alert you to any deficiencies or pH problems. Add organic matter: Adding organic matter is hands-down, without a doubt, the number one way to improve your soil. Whether your soil is clayey, sandy, low in nutrients, compacted, has poor drainage So what should you be adding to your soil?

Compost is a must--it will improve your soil immediately and introduce microorganisms that will continue improving your soil by further breaking down organic matter.

But in the long run, the success of your garden depends on making healthy garden soil. The more you can do to keep your soil healthy, the more productive your garden will be and the higher the quality of your crops. In the last issue, I discussed the value of soil care methods that imitate natural soil communities.

These include protecting soil structure, feeding the soil with nutrients from natural and local sources, and increasing the diversity and numbers of the microbes and other organisms that live in the soil. There are many ways to do this, but they all revolve around two basic concepts: For more fertile soil, you need to increase organic matter and mineral availability, and whenever possible, you should avoid tilling the soil and leave its structure undisturbed.

Add manures for nitrogen. All livestock manures can be valuable additions to soil — their nutrients are readily available to soil organisms and plants. In fact, manures make a greater contribution to soil aggregation than composts, which have already mostly decomposed. You should apply manure with care. Although pathogens are less likely to be found in manures from homesteads and small farms than those from large confinement livestock operations, you should allow three months between application and harvest of root crops or leafy vegetables such as lettuce and spinach to guard against contamination.

Also, if manures are overused, they can provide excess amounts of some nutrients, especially phosphorus. Because of this, it may be best to restrict fresh manures to heavy feeding, fast-growing crops like corn, and process additional manure by composting.

On the other hand, human manure requires cautious management to avoid spreading disease. Try composting. Composting is a means of recycling almost any organic wastes.

It reduces the bulk of organic materials, stabilizes their more volatile and soluble nutrients, and speeds up the formation of soil humus. The older I get, the more interested I am in an easier alternative. Instead, you can keep these two compost materials separate, and apply them in two layers directly to the garden bed. The second alternative is vermicomposting: using earthworms to convert nutrient-dense materials, such as manures, food wastes and green crop residues, into forms usable by plants.

Earthworm castings are a major part of my fertility program. I started vermicomposting with a 3-by-4 foot worm bin. Then last year, I converted the center of my greenhouse to a 4-by foot series of bins, 16 inches deep. My worms process horse manure by the pickup load from a neighbor. Not only do the worm castings feed plant roots, they carry a huge load of beneficial microbes that boost the soil organism community.

Tap chicken power to mix organic materials into the soil. Typically, I use electric net fencing to manage my chickens, rotating them from place to place on pasture. I dump whatever organic materials I have handy in piles, and the chickens happily do what they love best — scratch ceaselessly through that material, looking for interesting things to eat. In the process, they shred it and incorporate it into the top couple inches of soil, the zone of most intense biological activity.

Their droppings are scratched in as well, and they give a big boost to the soil microbes. As I explained in the previous article, when you first start gardening, it may be necessary to use rock powders, and other slow-release sources of minerals, to correct mineral deficiencies in the soil.

In the long run, however, you can supply minerals without purchasing inputs. The organic materials we add to our soil supply most of the minerals healthy crops need. The roots of comfrey, for instance, can grow 8 to 10 feet into the subsoil. Stinging nettle is another extremely useful dynamic accumulator. Both nettle and comfrey, in addition to high mineral content, are high in nitrogen.

They make excellent additions to a compost heap or can be used as mulches. If you have some pasture, think of it as a fertility patch par excellence. When growth is fast and lush in the spring, you should be able to take one or two cuttings, perhaps even more, for use in composting or as mulches.

In the spring, I allow some areas to grow about 8 or 10 inches before cutting it with the scythe and using it for fertility applications elsewhere. An example is yellow dock Rumex crispus. Why not allow some yellow dock to grow here and there, in edges and corners where it is not in the way?

When the plants start to make seed heads, cut them off just above the crown to prevent huge numbers of seeds from blowing loose in the garden, then use the plants in mulches or composts. Plant cover crops. Growing cover crops is perhaps the most valuable strategy we can adopt to feed our soil, build up its fertility and improve its structure with each passing season.

Freshly killed cover crops provide readily available nutrients for our soil microbe friends and hence for food crop plants. Plus, the channels opened up by the decaying roots of cover crops permit oxygen and water to penetrate the soil. Legumes clovers, alfalfa, beans and peas are especially valuable cover crops, because they fix nitrogen from the atmosphere into forms available to crop plants. Mixes of different cover crops are often beneficial.

For example, in mixes of grasses and clovers, the grasses add a large amount of biomass and improve soil structure because of the size and complexity of their root systems, and the legumes add nitrogen to help break down the relatively carbon-rich grass roots quickly.

Try to work cover crops into your cropping plans with the same deliberation that you bring to food crops. The easy way to do so is to maintain two separate garden spaces: Plant one to food crops and one to cover crops, then alternate the two crops in the following year. But most gardeners cannot devote that much space to such a strategy, so effective cover cropping must be fitted into a unified garden plan, a concept that in practice can get fiendishly complex.

Gardeners who like jigsaw puzzles will love the challenges.