During the light cycle, different wavelengths of blue and red light stimulate various plant functions from growth rates, flower formations, oil and scent production to the actual structure of the plant. But what wavelengths do what specifically? Luckily, some very smart people figured this out for us and we’ll go over that shortly.The better quality of light and the more leaf area exposed, the better the energy production, enabling the leaves to create and store as much energy as possible, as quickly as possible. This glucose energy is stored in the leaves throughout the whole plant. So take care when trimming those lower leaves, you may be removing possible “energy banks”.
When the plant has created and stored as much energy as it can, its “energy banks” are full. Anymore light after this time is potentially wasted. Enter the dark cycle. In this cycle, plants convert the glucose into more complex sugars (energy). Think of this process as digesting light. This is an important job, but the dark cycle still has more work to do.Plants are effected by the length of time that they are in darkness, not light. This is referred to as the photo period. The length of the photo period triggers a hormonal response that makes them want to reproduce (flowering/fruiting). So if we can control the length of time that a plant is exposed to darkness, then we can control its hormones… if only this was possible in teenagers.
Now, every plant is different, but most fall into 1 of 3 categories: Short Day, Long Day, and Day Neutral. It’s important to know which category your plant falls under when you’re programming your light timer. We don’t want that spinach to bolt, now do we?
Then you have to step up to a big, powerful, bad-ass High Intensity Discharge (HID) lamp. We know HID doesn’t really sound as cool as PAR, but we’ll take it. An HID system consists of 3 main parts: a ballast, reflector, and lamp.The reflector focuses the light in the preferred direction, making the light more efficient. They come in various shapes and sizes depending on how much area you want to cover. Always, always use a reflector.
The ballast is the driving force of the lamp, sending and controlling energy. It’s like the engine behind the bulb, without it no HID bulb can spark.
Of course, there are some drawbacks to HID lighting. A 1000W bulb can suck power from your house faster than a mosquito draining blood from a baby. HID bulbs also run very hot… like burn your plants hot. So please keep them 10-16 inches from your plants at all times. If you’re unsure how far, put your hand on top of your plants. If it’s too hot for you, it’s definitely too hot for them.You should replace your HID bulb every 60k hours, or once a year if used throughout. They tend to degrade over time, and your eyes may not notice a difference in the PAR spectrum, but your plants will. Keep it as a backup in case you run into an emergency situation.