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SolarSystem Spectrum Control – Suggested Settings and Hanging Heights

california led grow lights controller

When using SolarSystem series lights, we highly suggest utilizing the SolarSystem Controller to access all the features and capabilities of the lights. SolarSystem series lights are designed to produce targeted spectrums which are ideal for each phase of growth.

It’s important to understand that both spectrum and timing play a major role in how a plant grows. By giving your plants the right spectrum at the right time, you’re triggering responses in the plant which will translate to healthy and rapid growth, higher yields, and desirable terpene profile. The wrong spectrum or timing can easily stunt growth or damage an entire crop.

From hanging heights to spectrum control, here are a few tips to help you get the most out of your SolarSystem LED lights.

LED Light Hanging Height Strategies

Hanging heights can dramatically affect the amount of light that is actually absorbed by the plants. Understanding this is essential to getting the best results from our SolarSystem LEDs.

Basic Heights

First, these lights are very powerful and have a narrow beam angle that is designed to deliver maximum intensity for bloom. Unlike many lower power LEDs that can be placed very close to the plants, the SolarSystem LEDs are designed to be hung from 24” to 36” above the canopy to get the most even light spread without getting light burn. Higher power fixtures like the SolarSystem 1100 should always have a minimum distance of 36” from light to canopy. Lower power fixtures like the SolarSystem 275 can be hung as close as 18” from the canopy.

Minimum Hanging Heights Above Plant Canopy

SS-275 SS-550 SS-1100
Seedling 30” 36” 55”
Veg 24” 30” 48”
Flower 12” 24” 36”

Reflective Walls

Secondly, if you have reflective walls and you will not lose light off the sides of the canopy, it possible to go even higher. The light will bounce off the walls and eventually be absorbed by the plants. This can offer deeper penetration into the canopy and better overall yield.

High Ceiling Commercial Grows

Finally, in a commercial grow with many overlapping lights and reflective walls, it is possible to go even higher. When a plant gets light from multiple sources, growth is multiplied and is much more even than lights closer to the plants. Very little light is lost off the sides and the plants get a more natural saturation of light from all sides.

Basic Spectrum Setting Strategies

The following suggestions should be used as a baseline guide for growing your crop. Due to variations in genetics, the ideal spectrum will differ from one phenotype to the next. These phases are discussed in more detail below.


A sunrise/sunset setting can be easily added to any light program. We strongly suggest using this feature with a 10-minute time period which is easily selected on the setup menu of the controller. Gradual transitions are much gentler on plants and reduce stress and stunted growth resulting from sudden environmental changes.

Propagation – Seedlings & Clones – Basic Suggested Setting – R39 W49 B99

Use a lower light level over all with high Blue-to-Red ratio for young plants. You can adjust the overall light level up or down depending on how your plants react, but we suggest keeping the above spectrum ratios. As soon as plants have at least two sets of true leaves you can gradually begin to increase the light level towards the full veg level below. Reducing Red reduces stretching but some amount of Red is essential for root development and balanced growth. The light timer setting should be 18 hours on and 6 hours off – some growers prefer 24 hours on and this works as well.

Vegetative Phase – R49 W99 B99

Full power to Blue and White with reduced Red. Red will cause unwanted stretching. Blue will result in less spacing between the nodes and shorter, bushier plants. You can actually change the height and shape of your plants in veg by adjusting the level of Red-to-Blue ratio. The light timer should be 18 hours on, 6 hours off. The time in veg depends on the size of the plants you want to put into flower.

Pre-Flower – Transition to Bloom – R99 W99 B50

Gradually increase Red while decreasing Blue as a transition to Bloom. The plants need time to harden off and gradually replace the heavy Blue light with heavy Red light. Going too fast in the transition from Veg to Bloom can shock the plants. The light should gently transition from 18 hours on and 6 hours off to 12 hours on and 12 hours off. Preflower should begin a week prior to shifting to Flower. This can be in steps or all at once as a transition period between Veg and Bloom. For a more advanced programmed transition from Veg to Bloom see below.

Flower – R99 W99 B39

After the Pre-Flower phase, shift to high Red and White and lower Blue levels. High levels of Red in bloom increase yield. High levels of Blue in bloom will divert plant energy to the leaves and actually reduce yield and produce fluffier buds. This is why indoor flowers are so much tighter and bigger than outdoor crops. Lights should be 12 hours on and 12 hours off. Flower time can take from 8 to 12 weeks depending on the strain. You may need to experiment with each strain to determine the best time to harvest.

Final Finishing – R39 W99 B99

Approximately two weeks before Harvest, gradually reduce Red and increase Blue. This will improve potency. For some more advanced finishing strategies please see below.

Advanced Settings

Here are some strategies we have received from growers over the years. These require a bit more programming but should not take longer than 20 minutes for even the most complex programs.

Gradual Transition from Veg to Bloom

A gradual change from Veg to Bloom will put less stress on the plants and better mimics nature. Rather than switching from Veg to Pre-Flower and then to flower in single steps, this can be done over a 5 to 7-day period. Here, the Red level slowly goes up and Blue level slowly goes down over 5 to 7 days to reach the Bloom spectrum. At the same time, the length of the day gradually shifts from 18/6 to 12/12 over several days as it does in nature. A sudden shift from heavy Blue to heavy Red as well as a sudden shift from 18/6 to 12/12 will shock plants and stunt growth for several days until the plants adjust. This is huge if you can do this more naturally. You can do this by programming more steps on the controller and adding more days in the calendar.

Gradual Transition from Bloom to Final Finishing and Harvest

In the same way that a gradual shift from Veg to Bloom improves plant health and yield, a gradual shift from Bloom to Final Finishing can also boost quality – especially smells, resin development and chemical profiles. Here there is a gradual shift from high Red to high Blue during the last one or two weeks of bloom. Some growers also like to gradually shorten the length of the day during the last week all the way to total darkness at the last day before harvest. This process diverts all the plant’s metabolism to resin development and most of the yield has already been obtained.

Finish with All Blue

Another popular strategy is to finish with all Blue during the last 1-3 days. Blue light seems to drive the chemical profile of the plant while Red is more associated with weight. Heavy Red will generate the maximum yield while a shift to Blue at the end of Bloom will improve quality – the best of both worlds.

Use Supplemental UVB for the Last Two Weeks

The more trichomes your plants produce, the higher their potency. Your crop produces trichomes primarily as a natural filter of UVB light. UVB can damage the plant’s reproductive cycle, and trichome production is a very effective protective mechanism. Your plants have a natural receptor which tells the plants how much UVB is in the sunlines. When the plant senses high levels of UVB, it pushes the plant to produce more trichomes. Thus, introducing higher levels of UVB during the later stages of Bloom can increase potency by as much as 25%. California LightWorks sells a supplemental UVB light for exactly this purpose.

At California LightWorks, we combine extensive knowledge of successful growth with insights from customers to provide the most comprehensive lighting solutions possible. Our SolarSpectrum LED lights are designed to help you get the most out of the LED spectrum. If there’s anything more we can do to help you with your lighting setup, please do not hesitate to contact us. We’re always happy to hear from our growers.


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