Frost Protection

Protecting crops from frost.

Unexpected spring frosts can kill young plants or cause irreparable damage to the flowering gardens and young ovaries. In the autumn term early frost can destroy the harvest is not yet.

Studies conducted by leading research institutions, for example, New Zealand Agricultural Engineering Institute, US department of Commerce and Volcani Institute in Israel have shown that one of the most effective methods to combat frost is to spray water over the plants with special sprinklkrov.

The level of protection can be obtained when the total amount of water sprayed sprinklers amount of water equal to 2-4 miilimetra rainfall per hour.

Sprinklers simulate rain, and freezing water, giving its heat, keeps intact plants.

Frost protection system should be included when the air temperature drops to +2 degrees Celsius.
It is desirable to monitor the temperature of temperature sensors are connected to an automatic system comprising a water supply.

When the air temperature above + 2-4 degrees the system is turned off.

The effectiveness of this method of plant protection repeatedly tested and is widely used in regions prone to late spring and early autumn frosts.

Operating principle.

The principle of operation of such a system is based on the fact that water freezes at 0ºC and gives the environment a significant amount of heat energy during the transition from one state - the liquid in the other - hard.
Plants covered with a crust of ice that protects them from further cooling.
Why plants are not affected under these conditions?
The freezing point of water present in plant cells, a little below 0ºC by it contains dissolved organic substances and miniralnoy.
When the air temperature above 0ºC, the ice will melt without causing harm to the plant.

In the table below, are given recommendations on performance protection against frost, as applied to fruit trees.

Score the required irrigation is usually given in the specifications for the sprinklers.

Installation choices for protection from frost.

Such systems are mounted as overhead sprayers, and a bottom. We recommend placing sprayers to protect orchards above the trees, as shown in the top picture. sprinkler type selected by the diameter of the spray cone, which should be 10-20% larger than the diameter of the crown of protected trees.

To protect vineyards sprinklers are used which are fixed on the trellis, in its upper part. For vineyards developed special types of sprinklers, creating a flame sprayed water directed along the rows of vines. Photo on the right.
For the protection of vegetable and flower crops sprinklers are placed on the field with an interval, which allows to create a continuous spray of water over the entire protected area.
It should be noted that effective spraying is necessary to have sufficient water pressure in the redundant system. For each type of dispensers usually necessary pressure is 2-3 atmospheres. Required water pressure is given in the specifications for each individual sprinkler.

Additionally, for example, sprinklers flipper type to which water is fed via small diameter tubes, must take into account that at low temperatures, to avoid freezing of the water supply pipes, the water temperature should be at, a high possibility. It is recommended to use water with a temperature of 15-20 degrees.

For systems where the water is supplied through pipes of large diameter, to water temperature requirements are not as critical.

Special sprinklers for frost protection.

Sprinklers are developed, allowing to carry out effective protection against frost.
The peculiarity of such sprinklers - low water consumption, a large protected area of the landings and the possibility of reliable operation at low negative temperatures.

The following table shows some types of sprinklers are recommended for this purpose.

A type	Model	The diameter of the irrigation	water consumption	Indicator precipitation. mm / hr
	861	5,5-10 meters	35-160 l / h	1,1-3,9 mm / h
	700	3,1-5,9 meters	40-160 l / h	4.0-7.0 mm / h
	920	15-16 meters	227-503 l / hour	1.3-2.7 mm / h
	Flipper	The distance between sprinklers 6-9 meters, zaisimosti from the nozzle size.	23-40 l / h	Of the estimated rate of 4 mm / h, due to the original design, saving 50 to 65% water.

Mounting (installation) Sprinklers:

To protect orchards and vineyards is recommended to install sprinklers directly to the pipe diameter of 1 / 2-3 / 4 inches, and placed at the top of the pipe.
If this is not possible, then the tube is placed on the ground level and the water to the sprinklers fed by pipe diameter of 1/2 inch, as in the photo on the right.

To protect the vegetable plants sprinklers must be raised above ground level to a height of 80-100 centimeters.

For pipelines recommended plastic pipe (in any case no metal!) 3/4 - 1.0 inch.

Optional equipment.

Water Filtration System Works for such - a must!

Therefore, necessary to put the inlet filter.

The second important condition:
we must monitor the ambient temperature and automatically turn on the water at the critical temperature drops and off when the temperature rises above 1ºC.

This can be used with the temperature sensor controller and solenoid valves to control the water supply.