- The history of drip irrigation
- The structure and main characteristics of drip irrigation systems
- DIY drip irrigation
Water is the basis of life on earth. This substance is the main element of the biosphere, without which organic nature is unable to exist. The human body consists of water on average by 70 percent, and it is simply impossible to imagine the vital activity of any living organism without this unique compound. The plants that we grow on our backyards cannot do without water.
We talked about how to “water” garden crops so as not to harm them in the article “Watering the Garden Properly”. Unfortunately, an acute shortage of fresh water is felt today practically throughout the entire territory of our planet. This suggests that water must be conserved and used very sparingly. It is for these purposes that drip irrigation systems were invented, which allow maintaining the necessary soil moisture while using a minimum amount of water. Today we will talk about where and when this invention was born, we will deal with modern designs and their main characteristics, and also find out how to design a drip irrigation system on our own from the materials at hand.
The main principle of any drip irrigation system is that water is supplied periodically or constantly, but very little by little, to each plant individually. At the same time, the earth never dries up, and the plants locate their root system in the zone of optimal moisture, without spending energy on the development of deeply stretched roots. The advantages of this watering method are undeniable:
- minimum water consumption in comparison with surface irrigation and sprinkling (these methods were described in more detail in the article “Watering the garden correctly”);
- water enters the beds slowly, so it is always warm, as it has time to warm up in the tubes;
- minimal labor intensity of the process – a person does not need to run with a watering can or a hose – you just need to open the tap;
- plants and soil inhabitants never experience a moisture deficit, which favorably affects their growth, development and reproduction.
In arid countries (Israel, the United Arab Emirates), where the shortage of fresh water is especially acute, everything is watered in this way, from flower beds to palm trees on the beaches. It was Israeli inventors who patented the first drip irrigation systems, thanks to which this desert country turned into an importer of crop products in less than a decade..
The history of drip irrigation
The idea of local soil moistening first appeared in Germany at the end of the 19th century (1860-1880) – at this time, German inventors carried out a number of experiments using ceramic pipes with small branches. In the 30s of the twentieth century, these ideas were taken up by the Israeli agronomist-innovator Simha Blass. It was he who designed the first dropper, the structure of which differs from modern ones very slightly. Today Blass is considered the inventor of the drip irrigation system..
The use of drip irrigation systems on an industrial scale began much later, and the impetus for this was the invention of low and high pressure polyethylene (1935 and 1948, respectively), on the basis of which the production of plastics began. In 1963, the first patent was issued in Israel for the invention of a modern drip irrigation system, in 1964 a similar irrigation system appeared in the United States. Since then, there has been a systematic growth of agricultural land irrigated in this way. Today, the use of local irrigation systems is widespread in Israel and the AOE, in the United States and Australia, as well as in Germany, Spain, France, Austria, Egypt and other countries. The popularity of drip irrigation is growing from year to year, and today there are about 3 million hectares of agricultural land around the world, on which drip irrigation systems of different characteristics and indicators are used to moisten the land.
The structure and main characteristics of drip irrigation systems
After the invention, the use of drip irrigation systems became widespread, first in the greenhouse industry, and then it began to be used in the open field for growing vegetables and fruits. Today, local moistening of the earth is also widely used for watering vineyards..
Modern drip irrigation systems are flexible hoses with built-in drippers that equalize the water flow along the entire length. Such hoses are laid on the surface of the soil, or buried in it over the entire required irrigation area. Today on the market of goods for the garden-garden there is a wide selection of drip irrigation systems from various manufacturers, but there is no fundamental difference in design. The drip irrigation system consists of the following mandatory elements:
- Water intake unit. These can be various containers, raised to a height of 1–2 meters. The water from them is supplied either by gravity or using suitable pumps. The source of water can be a river, a pond, a lake, a well, a well, as well as a water supply. Everything here depends on your desires and capabilities..
- The filtration unit is an extremely necessary element of the system, on which its performance and durability directly depend. Filters purify water and prevent droppers from clogging.
- The main pipeline is made of polyethylene or PVC pipes with a diameter of at least 32 mm, on which fittings for drip tape are mounted. In its simplest form, a regular garden irrigation hose can be used as the main pipeline. The only condition is its mandatory opacity in order to prevent the growth of algae inside the system.
- The distribution pipeline is a line-tube with droppers installed in them during the production process. Drippers come in various shapes (flat or cylindrical) and are spaced at a certain distance from each other, which varies from 10 to 100 cm.
- Connecting fittings and fittings are needed to connect all the above-described elements into a common system. Both threaded connections and adapters can be used here. To connect the system to a water source and when installing the system on the beds, various tees, corners, transitions, couplings, plugs and fittings are used. Fittings can be with or without taps. Faucets are used to water crops that require varying amounts of moisture. When assembling drip irrigation, do not use accessories made of ferrous metals, as they are prone to rust formation, clogging the system.
The drip irrigation system can be made from either drip tubes or drip tapes. Drip tubes are polyethylene pipes with a diameter of 16 to 20 mm with a wall thickness of 100 microns to 2 mm. The droppers are connected to the tubes either externally or integrated from the inside. Drip tapes are made from strips of polyethylene rolled into a tube and connected, in most cases, thermally. The droppers in this case are the micro-holes left free during gluing / welding. Wall thickness of drip tape ranges from 100 to 300 microns.
Drip tubes are designed for relatively high pressure (0.5 to 4 atmospheres) and long term use. They are usually used for irrigation of gardens, vineyards, various elements of landscape design. Drip tapes are designed for use at low pressure (0.2-0.5 atmospheres) and are mainly used for watering vegetable beds.
One of the main characteristics of drip irrigation systems is the presence of compensated or uncompensated drippers. Drip pipes with compensated drippers do not depend on the water pressure drop in the system and always give out the same volume of water per hour, which is declared by the manufacturer in the description of the technical parameters. Uncompensated drippers at different pressures in the system can deliver different amounts of water.
Modern drip irrigation systems can be equipped with automation, which makes it possible to accurately dose the amount of water for each individual bed, organize fractional irrigation. A connected rain sensor will block the water supply if there is sufficient rainfall. With the help of automation, you can turn on watering at a convenient time, for example, at night, when there is water in the water supply system. Naturally, such a pleasure requires certain financial investments. However, when installing and configuring automation, the system will work without your participation, which will make it possible to be absent from the personal plot for a long time..
Today there are no problems with the purchase and connection of drip irrigation, in specialized stores you can purchase all the necessary materials and equipment for installation, and the price range here is very wide – it all depends on the quality of the materials used and technical characteristics, as well as on your desires and financial capabilities. However, it is not at all necessary to buy a drip irrigation system in a store; if you wish, you can try to make it yourself. Some home garden enthusiasts have built homemade systems using all the materials at hand..
DIY drip irrigation
For the installation of homemade structures, you can use a variety of plastic pipes or flexible hoses. In this case, the following conditions must be observed:
- the water supply for irrigation should not exceed its output through all openings, otherwise it will not reach the last droppers, but will pour out through the first;
- from the previous paragraph it follows that the droppers should be narrow, but not too narrow – the needles from the syringes become clogged, for example, in one or two days.
It is possible to assemble a reliable, efficient and fairly convenient drip irrigation system from flexible soft medical hoses. The main hose should be 1–2 cm in diameter, and the same medical systems used are suitable as droppers. In this case, the needles should be used not thin (which are stuck into the vein), but thick ones used for bottles of solution. You will also need tubes to be put on these needles (half a meter for each will be enough). The needles are inserted obliquely into the axial hose, tubes are put on them – the system is ready. Such droppers do not often get clogged, and if this nuisance occurs, then it is convenient to clean them. The above design has only one drawback – transparent tubes in the sun quickly become overgrown with algae, but this problem can also be solved by covering the system with black polyethylene or placing it under mulch from available materials. We talked in more detail about mulching in the article “Organic farming. Let’s make the earth good “.
The installation of such a home-made structure, ideally, begins with the fact that they mark out the planting plan, determining the length of the ridges and the distance between them. However, if your beds are fairly even, then you can install drip irrigation using ready-made plantings, focusing on each individual plant. We cut off the tubes of the required length, connect them into a system. When placed on the beds, it is better to give the tubes a slight slope by fixing them on pegs. It is not recommended to assemble a system of great length – we make a line no more than 6-8 meters. In the right places we punch holes for droppers and insert needles with tubes there. After installation, we check the operation of drip irrigation under pressure; the water flow rate can be adjusted by changing the slope of the axial hoses. To effectively retain moisture, the garden bed must be mulched with a layer of organic matter of at least 3-5 cm.
The main problem of using the above-described home-made drip irrigation system in practice is that if water is supplied sparingly, then it does not reach the last droppers, but pours out through the first. If you increase the pressure, then all the holes work, but it takes a lot of water – the plants do not need so much. This problem can be solved by feeding water in portions using a dispenser.
The dispenser can be made from a 2 liter plastic bottle. We hang the bottle upside down, tightly insert a piece of a tube 5–10 mm in diameter into the lid and insert 30 cm inward. Inside the bottle, bend the tube with a loop so that the fold is located at the bottom (which is now on top), and the end almost rested against the lid neck. It turns out the so-called siphon. The piece coming out of the lid is connected to the drip irrigation system. We make two holes in the bottom of the bottle: one for a tube through which water will be supplied from the container, the second in the form of a narrow slot (so that insects do not get in) will be intended for air outlet. We supply water to the dispenser through a thin tube 1–3 mm in diameter.
The dispenser works very simply. As soon as the bottle is full, the water is discharged into the system through a curved siphon tube and distributed to the droppers.
The above home-made system is quite simple and cheap to manufacture, but it has a number of disadvantages, the main one being the need to constantly monitor it, to clean clogged droppers. Therefore, it is suitable for those gardeners who have the opportunity to spend a lot of time on the site. In order to reduce the risk of clogging, it is necessary to put a filter at the inlet – for this it will be enough to put a piece of foam rubber on the hose located in the container, which, if necessary, can be easily removed and washed. To prevent algae from growing, they need to be deprived of sunlight. To do this, the container is covered with a lid, and the transparent tubes are covered with foil. There are, of course, a lot of problems, but what a pleasure it is to watch how a system made with your own hands water the garden itself.
Scientists believe that drip irrigation is by far the most progressive and effective method of irrigation, especially in areas where there is an acute shortage of fresh water. In addition to economy, this irrigation method has other indisputable advantages, the main of which are low labor intensity and the possibility of full automation, purposeful and, if necessary, constant water supply for each plant, as well as respect for the soil and its inhabitants. The popularity of the drip irrigation system is growing from year to year, many gardeners, having evaluated all the pros and cons, realized that the monetary costs of purchasing it cannot be compared with the benefits that can be derived from its use.