Growing your food produce is one of the most rewarding things you can achieve. It can be demanding, and requires commitment but rewards you with an extraordinary amount of satisfaction. And today, it’s exciting to have control over how the food you eat is grown.
Plants grown for food, differ from ornamentals, in one respect, that harvesting the crop, continually removes nutrients from the soil. It is imperative then that we understand our soil, it’s structure, and know how to nuture it, adding value to it, through recycling where possibly (example, making compost), adding fertilizers and nutrients, tending to plants, protecting them from competition, (weeds), and attack from pests and disease.
Growing plants is easy, they require little more than nutrients, water and sunshine. To get impressive results, improving productivity, requires a little more committment.
Providing your plants with watering, maintenence, and feeding makes your plants stronger and more resilient to disease and garden pests.
Providing your plants with the ideal soil structure is the key. It is good gardening practice to think of soil structure as the foundation of a productive garden.
Soil supports and sustains plants, providing anchorage and a source of nutrients and water. You might be lucky to have a garden site with soil naturally suitable for food crop production, or you may have to make it yourself through cultivation and conditioning your soil.
The ideal soil is fertile, well drained loam. However, often, we have to contend with cold, heavy, and poorly drained clay or light, sandy soil, prone to rapid drying and loss of fertility.
Luckily, these less than ideal soils, can be improved. And even if this can not be done for some reason, some fruit and vegetables thrive while grown in raised beds or containers.
All soils are a mixture of weathered rock, rotted plants and animal remains or waste, (organic matter) and supports a miriad of organisms, whose’ life cycle makes the soil into a living medium.
The average gardener need not worry about understanding the complete science behind soil but it necessary to be able to identify the soil type on which your fruit and vegetables need to be grown. As to identify the different soil types and the different attributes of each type, which therefore affect plant growth and require different ways of cultivation and maintenence of your plot.
There are five basic soil types or textures.
Clay soil has the smallest particles among the three so it has good water storage qualities. It’s sticky to the touch when wet, but smooth when dry.
Due to the tiny size of its particles and its tendency to settle together, little air passes through its spaces. Because it’s also slower to drain, it has a tighter hold on plant nutrients. Clay soil is thus rich in plant food for better growth.
Silty soil has much smaller particles than sandy soil so it’s smooth to the touch. When moistened, it’s soapy slick. When you roll it between your fingers, dirt is left on your skin.
Silty soil retains water longer, but it can’t hold on to as much nutrients as you ‘d want it to though it’s fairly fertile. Due to its moisture-retentive quality, silty soil is cold and drains poorly.
Silty soil can also easily compact, so avoid trampling on it when working your garden. It can become poorly aerated, too.
Sandy soil has the largest particles among the different soil types. It’s dry and gritty to the touch, and because the particles have huge spaces between them, it can’t hold on to water.
Water drains rapidly, straight through to places where the roots, particularly those of seedlings, can not reach. Plants don’t have a chance of using the nutrients in sandy soil more efficiently as they’re swiftly carried away by the runoff.
The upside to sandy soil is that it’s light to work with and warms much more quickly in the spring.
Chalky or calcarous soils more often than not, are very deficient in plant food and rather shallow. They are often very lacking in humus, and as much organic matter as possible should be added every year. They are more often calcareous by reason of the fact that they overlie chalk or limestone, and the fine particles of these substances may be found every time the land is cultivated. When wet, they are often very sticky and unpleasant, and so are difficult to work during rainy periods. In dry seasons they are disappointing, as they soon suffer from lack of water.
Peaty soil is dark brown or black in color, soft, easily compressed due to its high water content, and rich in organic matter. Peat soil started forming over 9,000 years ago, with the rapid melting of glaciers. This rapid melt drowned plants quickly and died in the process. Their decay was so slow underwater that it led to the accumulation of organic area in a concentrated spot.
Peat soil tends to be heavily saturated with water, once drained, it turns into a good growing medium. The most desirable quality of peat soil, however, is in its ability to hold water in during the dry months and its capacity to protect the roots from damage during very wet months.
Peat contains acidic water, but growers use it to regulate soil chemistry or pH levels as well as an agent of disease control for the soil.
When wet peat soil is rolled, you won’t form a ball. It’s spongy to the touch and when squeezed, water could be forced out.
The Ideal Soil Type: Loam
The term ‘loam’ isused to suggest fertility and soil that is great for growing plants.
The type of soil that gardens and gardeners love is loamy soil. It contains a balance of all three soil materials– silt, sand and clay– plus humus. Because of its previous organic matter content, it has a higher pH and calcium levels.
Loam is dark in color and is mealy– soft, crumbly and dry– in your hands. It has a tight hold on water and plant food but it drains well, and air moves freely between soil particles down to the roots.
The feel test for loam yields a smooth, partly gritty, partly sticky ball that crumbles easily.
There is clay loam, silt loam, or sandy loam, depending on the basic soil type; silt, clay, and sand describe the soil texture, based on the mineral particles found in them. Mineral content of a soil is generally fixed by its original location, and the structural nature is fixed by the occurence of stones or gravel, and also by the addition of lime and organic matter.
Soil stucture and fertility.
If plants are to thrive, a soil must have good structure. Soil structure is measured by it’s tendency to form crumbs of mineral particles and organic matter held together with humus.
Well-structured soil is easy to cultivate, and has air spaces that facilitate aeration, and allows movement of water (carrying nutrients), the structure of the soil also affects the temperature of the soil.
Frost, and alternating dry and wet seasons, are factors that create good soil structure. However, compaction by excessive traffic, and cultivation in continued wet conditions can contribute to damaging the structure of the soil. Aeration can be damaged by continual winter rain.
Good drainage is also important and soil structure has a lot to do with drainage. Waterlogged soul becomes cold and lacks aeration.this prevents nutrient uptake and leads to plant roots becoming deserved or even dying.
One essential component of soil is humus.
The term usually refers to the organic content of the soil, from flaura and fauna. The humus, is a complex mix of compounds that derive from the decay of this organic matter. Humus, is crucial in the retention and release of nutrients, the formation of soil structure and directly affects the soils’ ability to hold moisture.
There is a wide range of living organisms that populate the soil and contribute to its fertility and structure. These include beneficial bacteria and fungi, and a range of microscopic worms and mites, besides the visible, like centipedes, beetles and earthworms. All of these insects and microorganisms, rely on organic matter, which they use to break down into humus. Adding organic matter to soil is one way to boost poor soils conditions.
Compost is a way of recycling your kitchen and garden waste that provides the garden then rich source of humus. Compost is a valuable source of organic matter, often on site, and maintains the fertility and improves of the soil.
Most fruits and vegetables grow reasonably well on a wide range of soils. Soil nutrients come from several sources- weathering of minerals, breakdown of organic matter, chemical reaction in the soil and absorption from the atmosphere.
The essential plant nutrients required in the greatest quantity are nitrogen, phosphorus and potassium.
- Nitrogen is absorbed in quantity by plants to promote growth leafy vegetables use a great deal as do blackcurrants plums in the fruit crops.
- Phosphorus is necessary for chemical reactions within the plant and is vital for cell division and the development of shoots and roots.
- Potassium, is essential in plant metabolism, giving hardiness, steady growth, disease resistance, and colour and flavour in vegetables and fruits.
- Magnesium, needed in photosynthesis, Calcium, facilitating growth, and Sulphur, needed for protein of cells, also have essential roles, but are required in smaller amount.
- There are also trace elements or micronutrients. The most important of these are iron, manganese, copper, molybdenum, boron, zinc, and chlorine.
Most fertilizers on the market have the major nutrients, nitrogen, phosphorus, and potassium in differing combinations The organic gardener can also influence nutrient level by applying organic fertilizers and manures, also organic matter such as compost.
Total absence of a nutrient from soil is rare although low nutrient levels can be a result of leaching by rainfall of flooding or through depletion by successive crop planting over time, a significant cause of deficiency in the soil can be due to the effects of acidity.
Lime is a vital soil ingredient in the organic garden, it affects the fertility in several ways. Lime is itself a source of calcium and essential major element for plant growth vital to the production of Good Soil structure
The presence of lime governs the acidity of the soil the more light the less acidic is the soil this affects microorganisms that break down the organic matter which sorry can not survive in the soil that is very acidic.
Lime is valuable on the structure of clay soils as it helps break down the clay and create soil structure that has increased aeration for effective water and nutrient retention. The PH also influences the activity of microorganisms and worms, especially bacteria. These decrease as the acidity of the soil increases.
The acidity of the soil affects the availability of nutrients and so, by modifying the soil’s acidity by applying lime, is an effective means of influencing nutrient availability.
Knowing you’re soils PH.
Use a pH soil testing kit, when planning your garden, to check soil pH, and to rectify any imbalances.
The degree of the acidity of a substance is measured on a graduate system known as the PH scale. At the middle of the scale, ph7 represents the neutral condition, values lower than this down to pH 0, indicate increasing acidity, and values above 7, up to pH 14, indicates increased alkalinity. Garden soils usually have a ph between 4.5 and 7.5 Most of the crops to be grown in a fruit and vegetable garden will do best on soils around 6.5 pH. This standard remains constant and is the level for which you should aim.
It is much easier to reduce the soil acidity than it is to raise it.
Take care with how you apply lime. Lime is available in three forms, quicklime, which is dangerous and caustic, hydrated lime, which is fast acting, but can damage foliage, and crushed rock, or ground limestone, the least hazardous, and the least expensive.
Rate of application.
To bring an acidic soil to pH 6.5. The amount applied will vary, not only according to the existing PH, but also to the soil type. The chemistry of the clay soil, makes it far more resistant to the effects of liming, than a sandy soil.
Whatever quantity you need to apply, for best effect, will be obtained, while applied well before planting. Ideally, this will allow the lime to initiate changes in the soil gradually.
Also apply lime after spreading animal manures.
Manures and fertilizers.
Most previously cultivated garden beds, have adequate levels of nutrients, with the exception of the levels of lime.
Crops make certain demands on soil, vegetables and fruits require more nutrients than ornimentals.
The organic gardener can add insurance by applying organic fertilizers and manure sources, which contain nitrogen phosphorus and potassium as a base dressing before planting.
As with good site preparation an annual topdressing of organic fertilizers and manures becomes invaluable.
Soil of any texture also benefits from the presence of organic matter which increases the humus content encourages worm activity improves soil structure and in turn it’s capacity to hold water and air it’s temperature and it’s drainage.
Organic substances are those derived from decomposed plant and animal remains and the waste products of animals inorganic fertilizers are derived from non-living carbon free sources including rock many vitamins committed to the principle of organic growing prefer organic products to the total and new exclusion of inorganic fertilizers, organic derivatives are much less likely to pollute the environment edible crops grown organically a more wholesome and a better flavour than those grown using other products.
Seaweed meal bone meal hoof and horn fish meal and fish blood and bone meal are widely available forms of organic fertilizers that are concentrated and have and can be long recommended bed preparation.
Feeling for top dressing fruit and vegetable crops dried blood (blood and bone) has excellent effects and many Organic Growers advocate the use of extract of comfrey and seaweed.
Check out my blog on how to make your own fertilizer using comfrey or stinging nettles.
Animal manures are mainly used as a soil additive they contribute to Good Soil structure and have important use as surface mulch. Nutrient levels are low but they are excellent for improving soil structure. if your supplies have not been left outside to break down for at least six months, before use, the fresh manure is likely to generate ammonia as it breaks down which can damage plants, generally speaking, the more well rotted, bulky, organic matter that can be worked into the fruit/vegetable garden at preparation time, the better.
Chicken manure has a high nitrogen content, whereas dairy cow and horse manures provide a more balanced boost of soil nutrients. Sheep and goat manures also provide needed nitrogen to soil, but they also add more potassium than dairy or horse manure.
Green manuring involves sewing a suitable fast maturing crop cutting it down you’re still young and digging it into the soil where it will be quickly releasing it’s nutrients into the soil and aiding the production of humus.
Green manures are usually sown in late summer or autumn and mop up any nutrients, preventing them being washed away by winter rain. When dug in the following spring, they release these nutrients right back into the soil.
Examples of green manures.
Any routes of compost is benificial, they all make excellent mulch, for fruit trees, canes, perennial veggies. Although it is surprising how much compost can be made on site in gardens, even a small garden can create a lot of compost for it’s plants. It is also easier than transporting manure from source to your garden.
Making compost from garden refuse and kitchen scraps is a simple practice that is a valuable source of organic matter for improving quality of soil and maintaining fertility. The practice even in the smallest of gardens makes a positive contribution towards recycling and the idea of “towards zero waste”.
Composting the practical alternative to the use of animal manure as can be difficult for the kitchen gardener to obtain is rich in the source of humus.
It is where the natural breakdown of organic materials is axcelerated to create a rich growing medium.
Cool composting is using compost bins. They are easy to use and can be emptied every few months.
Making a large compost heap, is simple, it kills wed seeds, and reduces spread of plant diseases, you will not find many worms though. Heat living aerobic microorganisms do most of the work in a hot compost heap.
A well made compost heap can get to around 70 degrees celcius, or 158 degrees farenheight, within 3 or 4 weeks. It is benificial to turn the heap from time to time.
The speed of decay is determined by the nature of the waste. A heap that is well looked after can produce useless compost within six months.
Anaerobic composting is a method that allowing less air to penetrate. Complete rotting takes much longer, one or two years.
Such methods include the trench method where you bury you’re waste or another way you can compost in closed sacks leavine it to decompose over time.
Leaves can be collected in bags and left for over a year to decompose, producing leaf mould. The mould has a friable texture and is suitable for mulching and for use in potting mixes.
This is a method of composting cooked food in a bin with a certain activator. It creates a liquid fertilizer that can be watered down for application on plants.
There are Bokashi bins in my store. Look for more blogs on composting.
Worm fertilizer production, also known as vermicomposting, is ideally suited for home gardeners because worm compost bins require little space. The manure product left behind by worms is called worm castings, and it makes an excellent garden fertilizer. Worm manure provides a balanced source of phosphorus, potassium and nitrogen, as well as micronutrients; worm tea cam be added to watering can, and worm castings can be added to soil, it is a great way too fertilize your plants organically and cost effective.
Kits containing everything you need for your worm farm, can be purchased from my store or you can make your own worm farm using materials around you. Look out for another of my blogs on vermiculture.
If crops are grown in the same ground year after year, generations of experience have shown the growth and yield are greatly reduced. Rotating crops in sequence is a long established practice to prevent this. Crop rotation maintain soil fertility combats pests and diseases and keeps the soil well cultivated.
One advantage of leaving a gap of at least three or four years before growing the same crop in the site again is that it interrupts conditions that favour particular pests and diseases.
Second reason for using rotation is to meet different nutritional needs well planned rotation maintains fertility.
Legumes for example broad beans can extract nitrogen from the atmosphere and with what’s it called nitrogen fixing bacteria, then nitrogen is found in the soil. Then planting something like brassicas would take advantage of the nitrogen in the soil, as brassicas love nitrogen. Then root crops like potatoes, which require low levels of nitrogen can be grown after brassicas.
Alternating crops also sets up a regular pattern for maintaining ideal soil pH. Legumes benefit from ground rest with organic matter which lowest pH while brassicas do best in soil with a higher pH which discourages clubroot alternating manuring and liming with these rotating crops and shows the soil never becomes either to acid or too alkaline.
The third benefit of rotation is that it helps to control weeds and maintain Good Soil structure this is where the third group is particularly beneficial cultivation of soil for potato salad vegetables helps break up the ground and keep it open.
It’s a common practice to have three rotating fields and leaving a fourth one fallow.