Hydroponic lighting systems have come a long way since the early days of indoor gardening. Incandescent and fluoride bulbs used to be the industry standard, but those have given way to High Intensity Discharge (HID) systems and Light Emitting Diodes (LEDs). In this article we will discuss the pros and cons of each type of system, including cost efficiency and ease-of-use.
There are several factors to consider when choosing a lighting system for you indoor hydroponic garden. Intensity of the bulb and the favored spectrum of the bulb are the first things to consider. Intensity was once measured by “candlefoot”, where the brightness of the candle is measured one foot away from the plant. This unit of measurement is now referred to as a lumen, and one lumen equals one candlefoot. It has been estimated that an indoor garden requires 2000 lumens per one square foot of garden in order to achieve satisfactory growth. Most modern lighting systems can deliver this intensity with no problem, although your wallet may suffer a little. The spectrum of the bulb refers to the variety of the frequency of colors that the light produces. Plants require a blue/green light for vegetative growth and a red/orange light for flowering and budding. With these factors in mind, we can now decide on a lighting choice to fit our needs.
So what choices do we have? Incandescent bulbs provide great red light, but most of the energy produced is wasted through heat – not a good choice for an indoor garden, especially when considering the amount of electricity used. Standard fluorescent bulbs are not much better, even though they are cheaper to run.
Fluorescent bulbs have come a long way, and special “grow-type” bulbs are now readily available. The warm white bulbs provide a good source of red light, while the cool white bulbs provide a good spectrum of blue light.
HID lights are a better option than the two mentioned above, but are more expensive. They produce an extremely high output of light in a mixed spectrum making them perfect for an indoor garden. A current is shot into the bulb and when a certain voltage is reached, the gas ignites creating an arc and light. They are expensive to purchase, expensive to use, and tend to run very hot. They eventually burn out due to a higher voltage draw each time it is used, therefore ballasts are required to maintain proper voltage for startup, basic operation and limiting the amount of voltage the bulb can draw. The ballasts are not interchangeable between different manufacturers, definitely putting a notch in the “cons” column. Even with these drawbacks, HID bulbs currently reign supreme when considering an indoor garden.
Our last option is the solid-state lighting system known as LED, or Light Emitting Diode. Originally developed for the hydroponics Garden on the Space Station, these bulbs produce little to no heat, draw very little energy and can be tailored to produce a custom spectrum of light. Also, they produce more light as more electricity is run through them, making them the perfect choice for a smaller, more compact indoor hydroponic system.
So depending on how much space and the budget you have to work with, your options are pretty cut and dried, with LED grow panels being the best overall selection. Choose wisely, search the web for options and setup tips, and most of all get a hydroponics lighting system that will allow for maximum yield from your indoor garden while minimizing cost.