The main question of the absolute majority of growers in the summer is: "How do I cool my growing space?" And no wonder. If, in summer, temperatures reach 35 ° C, for example, and there is lighting in the growing room that heats the growing room strongly, this task is really difficult. In this issue, we will discuss some tips and hints on how to reduce the temperature in the steamy months to achieve the ideal temperature for plants. 

The ideal temperature for the growth and flowering phases during lighting is in the range of 24–28 ° C and during the night phase 18–22 ° C. 

In some cases, the plants can also withstand temperatures slightly above 30 ° C during the day, but only if you have a CO dispenser2which is not exactly the cheapest. Its owners use it mainly in combination with an air conditioning unit to make CO2 it was not wasted outdoors - therefore they draw air only minimally from the growing room, the air is so saturated with CO2 and circulates in the growing room. 

CO dispenser combination2 and air conditioning unit is the most ideal solution, but also the most expensive and most demanding on electricity consumption.

Using the air conditioning unit alone is the second most effective solution, but it is not for everyone. A grower who has a growing tent of say 120x120x200 cm and smaller, which is most hobby growers, does not want to lose even a bit of space in the growing tent. Air conditioning units with their accessories are usually quite large and occupy a large part of the growing area. Of course, there are also smaller air conditioning units that do not take up so much space, but they are not very efficient. 

The second disadvantage is the relatively high purchase price and high energy consumption. It varies depending on how large the growing space is and what air content needs to be replaced in the growing room. The greater this figure, the more power the air conditioning unit, of course. However, if the grower has a large enough growing space and is not afraid to invest, an air conditioning unit is the right choice for him. 

If we are still talking about more precise, but also more expensive devices that can reduce the temperature, we must not overlook the light sources as well. 

Currently, growing plants under LED lighting is very popular. LEDs and chips emit very little heat compared to sodium and metal halide lamps. For this reason, some of the growers switch to LED lighting either completely, in combination with HPS / MH, or only for growing plants in summer. Again, however, we encounter a relatively large disadvantage and that is the high purchase price. Unfortunately, price sometimes does not necessarily mean quality, and the LED lighting market is still bringing new products to the world, which can lead many growers to the point that they will not be able to decide which one to choose. It must be said that LED lighting is in any case the future of indoor cultivation due to its efficiency, luminosity and PAR radiation. Due to the constant progress in development, the future of this lighting is more than bright. 

Another type of lighting that is relatively new to the market and has been shown to heat little is CMH / LEC. This type of lighting heats less than HPS / MH, its price is not so high and recently it is very popular with growers.

If you already own HPS lighting, there is another way to reduce the temperature in the growing box with an adjustable digital ballast. This type of ballast over its electromagnetic predecessors has the advantage of offering control in the vast majority of cases. This means that you can, for example, regulate your 600W lamp to wattages of 250/400/600/660 W. By reducing the wattage, you will achieve a lower temperature, but at the cost of power loss. What are we going to talk about - if a grower has a high temperature in the box, he can never achieve a high yield and good quality, so it's definitely worth considering. 

The use of so-called cooltube is also a great help to reduce the temperature. Cooltube is an elongated glass tube in which there is a sleeve for screwing on the lamp and which has smaller pieces of reflector around the edges for better light reflection. This cooltube is hollow on each side - this is because a ventilation pipe is connected to it, which expels the warm air from the lamp out of the growing room with the help of a fan. The Cooltube can be connected both separately with a small axial fan and connected to the main exhaust fan and odor filter, if the grower owns it.

For larger spaces, large lampshades are also available, which are closed and again separated from the plants by glass, or also open lampshades, which have a hole in their reflecting surface for connecting a ventilation pipe.


"Currently, growing plants under LED lighting is very popular"

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