Shade cloths, what and how?

Are you considering a reflector and looking for the most suitable solution at the best price? What should you choose based on, and which parameters should you look at? Then you are in the right place.

The basic parameters of reflectors that should be taken into account when choosing are the reflector’s reflectivity, light spread and its uniformity, the illuminated area, and the recommended reflector power.

Reflector reflectivity is stated in % and indicates how much of the incoming light is reflected back from the reflector onto the growing area. Reflectivity itself is very important, as the discharge lamp shines half of its output upwards, away from the plant leaves, and the reflector reflects this light back to where it is needed. Every lost percentage therefore counts, and the difference between a basic and the best reflector can mean up to 10% lost light output, thereby causing a lower yield or higher consumption due to the need to use a more powerful light source. 

The cheapest reflectors have a value of around 80%. Typical examples are reflectors costing a few hundred, such as Hammer; in the lower mid-range, we reach reflectivity of around 90%, represented for example by Waveflector reflectors. The upper mid-range is represented, for example, by the WAVEflector Vegagreen range, which has reflectivity of around 95%.
The highest class is represented by reflectors from the Adjust-a-Wings brand and its derivatives, which in the top range have reflectivity above 97%, and all ranges also have the most even spread of reflected light. 

This brings us to the second parameter, which is light spread. Making use of all the light produced by your source (usually a discharge lamp or CFL fluorescent lamp) does not yet ensure even plant growth and its maximum use. Every reflector reflects a different light intensity to a different place, so one plant has more light than another, to which the reflector reflects less light. The differences can be as much as 50%, and given that the reflector reflects around 50% of the light output of the discharge lamp, the difference can be very significant and have a negative effect on the plant. One will have too much light and may start to dry out - information for reducing the temperature in the tent - while the other has too little light and its full potential is not being used.

Quality reflectors are also manufactured in several sizes, and it is necessary to choose one that best matches your growing spaces, just as we do not recommend using light sources with a higher output than the reflector is recommended for. Unless you have a specific reason for doing so, you will probably not achieve a higher yield, quite the opposite.

A specific type is CoolTube reflectors, where the discharge lamps are enclosed in a glass tube and allow outside air to flow around the discharge lamp directly out, thereby affecting the temperature in the grow tent only minimally. Given the need to exchange air for plants as well, this solution is particularly suitable where the grower is dealing with problems of excessively high temperature in the tent and normal ventilation is no longer sufficient.