4 Steps of Good Soil Management

I divide soil management into four phases: the first phase is testing the soil; the second involves the general soil conditioning and replacement of nutrients with organic matter; phase three involves the application of fertilizer; the fourth phase covers more specialized application of fertilizers for specific plant needs.

If you have moved into an established garden that is obviously growing good crops, or if you have decided to convert to organic methods and there are no nutrient deficiencies showing up in your garden, start with the second phase. However, unless you know the acidity or alkalinity, or pH value, of your soil, you should test it before you start.

1. Analyzing your soil

If you are starting out, especially on virgin soil, it is a good idea to have it tested at the outset so that you know where you stand. Soils that have been uncultivated for many years are often grossly deficient in one or other of the elements necessary for healthy plant growth. Chemical growers would then repeat this soil test every year using sophisticated equipment to ascertain the exact requirements of the next crop.

I have never believed that gardeners, however diligent, need to get involved in this. Once you know what you are working with, I don’t think that it is necessary; annual home pH testing is sufficient. It is best to send a sample of your soil away for professional analysis.

The kits for testing nutrient levels in soil that are available to amateur gardeners are not accurate enough to be worthwhile. Used regularly, they will indicate a trend but no more than that. There are plenty of reputable companies who will analyze your soil. You will find them advertised in gardening magazines.

They will be able to tell you the exact chemical makeup of your soil and, if there is a deficiency, exactly how much fertilizer you need to use to correct it. Remember, though, when you send the sample, to ask them to recommend organic fertilizers.

2. Using soil conditioners

This stage deals with the general soil improvement and replacement of plant nutrients removed by previous crops. It is here that there will be variation because it depends on how much, and what type, of organic material you have available to you.

First of all, it should be taken as given that all organic material not actually used in the kitchen is returned to the soil as compost, and that this should be supplemented by manure or some other purchased soil conditioner, as necessary. Organic matter should be dug in during the fall and spread over the soil as a mulch in the growing season.

This will increase the water-holding capacity of light soils and open up very heavy soils, as well as supplying all the nutrients. If you can put sufficient organic matter on to the soil, there may be no need to add any concentrated fertilizers.

However, it is difficult to define "sufficient" because the amount needed depends entirely on your soil, the weather, the plants you wish to grow, and so on. You need to have a great deal of compost and/or manure if you are going to avoid using concentrated fertilizers completely.

3. Adding general fertilizer

Not everyone can get sufficient supplies of manure or compost. This is, therefore, where concentrated fertilizers come in. If, for any reason, the manuring falls below the recommended levels, you will have to make up the nutrients "out of the bag." Use a general fertilizer such as blood, fish, and bone meal or pelleted chicken manure.

The application rates vary according to the soil and the plants you want to grow, so I have made recommendations in the relevant posts of this blog. In fact some crops, for example peas, can generally grow quite well without the addition of fertilizer, so there is no need to apply it.

Others, such as potatoes, will need extra. Most fruit trees and bushes will need fertilizer in the spring whether or not they are mulched with manure or compost, as will the ornamental garden. Where any trace element deficiencies have occurred in the past, I recommend that you give the soil a light application of kelp meal or calcified kelp pellets at the beginning of each season to make sure it does not happen again.

4. Using specific fertilizers

Some crops always need special treatment even when the manure and fertilizer levels are sufficient to start with. If, for example, you are growing tomatoes in the greenhouse, they will benefit from extra feeding and a potash fertilizer to encourage flower and fruit formation.

Leafy plants that remain in the ground for a long time, like spring cabbage, may need some extra nitrogen fertilizer towards the end of the winter. Plants such as raspberries are particularly prone to iron deficiencies when grown in chalky soil; this can be corrected by spraying and liquid feeding with kelp (seaweed) fertilizer. It is a good idea to apply extra phosphorus, or phosphate, before planting trees or sowing, to encourage root growth.

How to Improve Your Soil

There are various cultivation techniques that you can employ to improve your particular soil; these are discussed in the previous posts. All soil types will benefit from the addition of bulky organic matter in the form of compost or manure or some other soil conditioner.

This is the key to soil fertility, and a healthy, fertile soil is the basis of the organic approach to gardening. In fact it is the basis of good gardening, whether you are committed to organic principles or not. Organic matter will improve the drainage or increase the water-holding capacity of your soil. It will also, over a period of time, increase the depth of usable topsoil.

I have a perfect example of the value of organic matter in my own garden. My soil is a rich, dark brown color, fibrous and full of worms, a reliable indicator of the presence of healthy numbers of other less obvious life. Everything I plant seems to thrive, and the soil is a pleasure to work.

This is because it gets the benefit of hefty doses of manure and compost every year. Yet I need to walk only a few feet to the cornfield next door, which never sees any organic matter from one year to the next, to find a soil that is hard, compacted, and airless. It’s difficult to force a fork through the top layer of soil and, when you do, there’s not a worm to be seen.

Granted, there are monoculture farmers like my neighbor who still grow very good crops of wheat, year after year, without the soil ever seeing a forkful of manure. With no cattle on their farms it would be difficult to supply the manure and, in the interests of convenience and economy, they even burn the straw after the harvest. However, they do so at the cost of enormous inputs of chemicals and of a steadily deteriorating soil.

What Should You Use to Improve Your Soil?

There is no doubt at all that, if you put on sufficient well-rotted manure every year, your soil will remain fertile and your plants will prosper. But where is all the manure to come from, particularly if you live in a city? The days are long gone when you could follow the horse and cart with a shovel and bucket. And, if you live in the country, particularly if it is a corn-growing area, the farmer’s children don’t even know what cows look like.

So the gardener’s alternative is compost. But is that being realistic? Certainly it looks good during the early summer when you start to fill your compost container with grass cuttings. After a couple of mowings, it fills up to overflowing and you have to start another. Yet by the time it has rotted down completely, it has shrunk to no more than a few bucketfuls.

Using Store-Bought Material

In fact a normal-sized garden with a productive vegetable plot will simply not produce enough compost. You will have to buy some form of organic matter, and be constantly on the lookout for suitable composting material.

Naturally, the more you can gather, the better, because you will have to buy less. Even if you live in a city there are ways and means of doing this. Unfortunately it is almost impossible to garden totally organically, because virtually everything that you might use is polluted with some chemical or other.

Straw has been sprayed with weedkiller, fungicide, and insecticide; the cows have been force-fed with growth-promoting hormones; even the leaves swept from the pavements are polluted with lead from gasoline. So, if you are a purist— and I am—you may feel safer if you compost all imported material for at least a year in the hope that the toxins will be leached out.

Feeding the Soil

Plants need certain nutrients in specific proportions to be present in the soil. These nutrients will be supplied by the addition of sufficient compost or manure, but you may have to use organic fertilizers as well to achieve the required balance.

The techniques of feeding and the type of fertilizer you use to feed the soil will vary depending on your soil type, where you are, and how much organic matter is available to you. In addition, the degree of acidity or alkalinity, or pH, of your soil will affect the availability of some of these nutrients.

So, you may find that, having established the pH level and taken measures to adjust it if necessary, you release more nutrients, therefore increasing the fertility of your soil.

Handling Peat Soil

If you are lucky enough to be growing on peaty soil, grow as intensively as you can, as it is always potentially very fertile and usually easy to work. You’ll find it easy to produce bumper crops and beautiful flowers year after year. Properly managed, a peat soil is superb but, like other soils, it does have its problems.

Most importantly, peat soils are liable to be acidic and will therefore need generous applications of lime to restore the pH balance in the fruit and vegetable plots. In the ornamental garden, provided you choose the correct plants, this should not be necessary.

Furthermore, when they are drained, peat soils tend to dry out quite rapidly in hot weather. If they are allowed to dry out completely, they will shrink and may be difficult to get wet again. To prevent this, some hand watering may be necessary in dry weather.

Digging

The timing of cultivation is not critical. It is not necessary to leave peat rough during the winter.

Drainage

Moorland and fenland peats are often badly drained so you may need to install a drainage system.

Organic Matter

A major advantage of peat is that it is not normally necessary to add any humus-making materials. Peat, unlike the other soils, is largely made up of decomposed matter. It therefore has a low mineral content but contains an excess of organic matter. However, the soil is likely to be low in nutrients to start with so you may need to add fertilizers.

Handling Chalk Soils

There are two big disadvantages with chalk soils. Firstly, they are thin, dry, and "hungry". This is because the particles are very large, like those in sandy soil, so water drains through rapidly, taking plant nutrients with it. Plant nutrients, in the form of organic fertilizers, will therefore need to be added to the soil. Secondly, perhaps even worse, chalk is a very alkaline soil, and so unsuitable for many plants.

Digging

Generally there is no need to worry too much about the timing of cultivations. Like sand, chalk soils are normally dry enough to work, even in the depths of winter. It is not necessary to leave a chalky soil rough during the winter months for the frost and rain to break down. Instead dig it in the spring a few weeks before sowing. Because the topsoil is usually not very deep, digging should be kept shallow and, if the area is fairly small, it could be worthwhile adding a layer of topsoil to the surface.

Drainage

Generally, drainage on chalk soil is too good and the need is to retain water and nutrients. This can be done by adding bulky organic matter that will also help to acidify the soil.

Organic Matter

On chalk, more than any other type of soil, it is important to try and keep the soil surface covered. Grow a crop of green manure during the winter and dig it in during the spring. During the growing season, it is even worth sowing a fastgrowing green-manure crop between vegetables, just to keep the soil covered.

Mulching, or spreading organic material on top of the soil between plants, is also important during the growing season. You should use acid materials, such as peat, grass cuttings, compost, or manure, in order to counteract the alkalinity of the soil.

Handling Sand

A very light soil, sand tends to drain easily and can therefore be cultivated when other soils are lying sodden and unworkable. As it also warms up quickly, it is an ideal soil for raising early crops. However, sand is also hungry and very demanding. So the price of having an easy soil to work is the need to apply extra organic matter and plant food, in the form of fertilizers, because nutrients, as well as water, will drain away.

Digging

When you cultivate sand is relatively unimportant. It is not necessary to leave a sandy soil rough during the winter months for the frost and rain to break down. The large particles make it very easy to cultivate to a fine tillage anyway, so it is best to dig it in the spring a short while before you intend to sow or plant. If you never venture on the soil when it is so wet that it sticks to your boots, you will not go far wrong.

Drainage

During the year, sandy soil will tend to lose water, both through surface evaporation and free-draining, and this could be detrimental to the plants. To reduce the problem, spread organic matter, or mulch, over the beds between plants as often as you can. This lowers the evaporation rate and improves the soil structure.

Organic Matter

It is very important to improve sandy soils by adding substantial amounts of bulky organic material each year. Because of the quick-draining nature of the soil, the organic matter will work down into the subsoil very quickly so, to save work and to put it in the root zone, dig the organic matter into the top few inches or spread it over the surface.

Try to maintain a cover of vegetation over the surface more or less all the time, and certainly in the winter, when the "leaching" of nutrients is at its most rapid. In the vegetable garden, it is a good idea to grow a green-manure crop during the winter when the beds are empty and to dig it in during the spring. This will not only hold many of the nutrients in the soil during the winter, but will also add large quantities of organic matter.

Handling Silt Soil

The main problem with a silt soil, as with clay, is one of drainage. Of all the soils formed by grinding, silt has the smallest particles. Only the particles of clay are smaller, but they were formed by chemical action. The size of the particles means that they tend to pack together very closely when wet, preventing the free passage of water and air through the soil.

So drainage is poor and there is a danger of the soil settling down to form an airless mass. However, if you never walk on the soil when it is wet (use boards) and condition it as recommended here, silt is perfectly manageable and will produce satisfactory results.

Digging

Silt soil should be cultivated only when it is dry enough not to stick to your boots. Conditions underfoot permitting, aim to dig silt during the fall to take advantage of weather which will help break the soil down to a sowable tillage. Like clay, when silt gets wet and dries out again, it expands and contracts, causing the mass of soil to crack into small clods.

If water then gets into these cracks and freezes, it will force them further apart, breaking the soil down even more. So by digging silt over in the fall, you expose the maximum amount of the soil surface to the elements and work the organic material into the topsoil at the same time.

Drainage

In order to improve drainage, the soil particles have to be forced apart physically to allow free passage of air, water, and plant roots. Do this by digging one or two bucketfuls of coarse sand into the soil every square yard/meter when you dig in the organic matter. Raising your ornamental beds slightly and growing vegetables on the deep bed system will improve drainage, helping the soil dry out and warm up.

Organic Matter

The structure of silt soils benefits greatly from the addition of liberal quantities of well-rotted compost or manure. Adding plenty of bulky organic matter to the soil will hold the particles apart so that roots and water can pass through more easily. If possible, keep the soil covered with a green-manure crop in order to add organic matter and remove surface water.

Handling Clay Soil

While clay is beset with problems initially, a little work and sound management can produce excellent results. It is certainly true that, in the early stages of cultivation, clay is not nearly as convenient to work as a light soil such as sand. When it is wet, it rapidly becomes a soggy mess of mud and, when it dries out, it sets like concrete.

Clay is a badly drained, cold, and heavy soil because the spaces between each particle are too small to allow free passage of water and air, so the soil is always in danger of settling down to form a solid, airless mass. Improving the soil structure can take a few years, but a good clay soil is capable of growing far better crops than a sandy soil ever could.

Digging

It is best, if you can, to dig a clay soil during the fall, either at a time when there has been a little rain to soften the hardbaked soil, or when it is drying out after being soaked, but before it is hard again. In temperate climates, these times are fairly frequent, but in drier climates it calls for good organization and rapid action when the weather changes.

When heavy soil gets wet and dries out again, it expands and contracts, causing the mass of soil to crack into innumerable small clods. If water then gets into these cracks and freezes, it will force them further apart, breaking the soil down to a sowable tillage.

So dig clay soils in the fall, leaving the surface rough and uneven through the winter to expose the maximum amount of soil surface to the elements. At the same time, you can work the organic material into the upper levels.

Drainage

Because clay was broken down chemically, it’s also possible to combine the particles chemically by a process known as "flocculation". If sufficient lime is added to the soil, the tiny particles of clay will bind together to form much larger crumbs, through which air, water, and plant roots can freely pass.

Check the requirements of the plants you want to grow and use as much lime as you can without making conditions intolerable for them. In addition, if your soil is very heavy, dig coarse sand into the soil—approximately one to two bucketfuls every square yard/meter. Raising a section of soil above its immediate surroundings will improve drainage considerably, helping the soil dry out and warm up; raise your ornamental beds slightly and grow your vegetables on the deep bed system.

The important thing with clay is that you should never walk on it when it is wet or you’ll destroy years of work. If you have to walk on it, lay boards down first.

Organic Matter

Adding plenty of bulky organic matter to a clay soil will hold the particles apart so that roots and water can pass through. After a few years, when the level of organic matter is satisfactory and the soil is filled with the roots of previous crops, clay becomes much easier to work. In fact, every plant you grow plays its part in improving the soil for the next plant generation.