In our ongoing quest for bigger and better it is not always the mighty watt that needs to be increased. We all know that yield is based on a confluence of factors including: genetics, light intensity, light spectrum, proper nutrition, grower ability etc. However sometimes we find ways to advance our ability to grow plants by improving our equipment. To that end lets look at a less utilized type of metal halide lamp know as a Ceramic Metal Halide (or CMH.) CMH lamps use a ceramic composite material to make the arc tube (the cylinder inside of your bulb that holds the gasses & produces light when electricity is passed through it.) The problem had been that when using the ideal mixture of gasses the arc tube got so hot that it melted. This led to using different mixtures of gasses that do not get as hot; however as a trade-off they did not produce an ideal spectrum for photosynthesis.
That has all been solved with the CMH! The ceramic composite that the arc tube is constructed of can withstand 1,500 degrees Kelvin opposed to the older Quartz or PCA arc tubes that were only able to handle 1,300 degrees Kelvin. The increased operating temperature has allowed the bulb manufacturing companies to tailor the gases in the arc to provide a better spectrum of light for photosynthesis. This advent will let the light shine brighter and better on your garden with a simple twist of your bulb.
Here is what you need to know when considering CMH’s:
- ONLY use CMH lamps on standard coil and core HPS ballast.
- Ceramic Metal Halide bulbs can be used in BOTH vegetative and bloom cycles.
- They should not be operated with digital ballasts. CMH bulbs cannot handle the high frequency vibrations caused by digital ballasts.
- CMH lamps are known to increase vegetative growth so much that you may want to implement the use a Potassium Silicate fertilizer supplement (i.e. Silica Blast.) Silica fertilizers strengthen plant cell walls, thereby making the plant’s leaves, stems and branches thicker and heavier as well as better able to support heavy clusters of fruit.