Lighting is one of the most important components of an indoor gardening set-up, and in today’s competitive and somewhat flooded market, making the right choice for your garden can be quite overwhelming. Fortunately, we know the right questions to ask to help you make an informed decision. We often recommend LED to growers that want a low profile set-up. LED’s generate less heat and draw less power so they are easy to fit into smaller spaces with very little ventilation needed. One other consideration is that LED diodes last considerably longer than typical HID bulbs, giving them a life expectancy advantage over anything else. For example, most HID bulbs will peak out at around 24,000 hours before needing to be replaced, while the LED usually comes in at around 50,000. This makes LED a great option for a hobbyist that wants minimal maintenance regarding replacements and upkeep.
We recently picked up the AgroLED Dio-Watt from Sunlight Supply and have tested it in each of our stores. So far, the results have been great. What’s nice is that they make the unit in 4 different sizes to accommodate many footprints. Each unit contains two switches to determine vegetative or blooming spectrums. The vegetative switch controls the blue spectrum (great for leafy growth) and the bloom switch controls everything else. We recommend using just the veg spectrum when introducing young clones or seedlings and then turning on the bloom with the veg as soon as the plants acclimate to the light, giving your plants a well rounded full spectrum. If you have never seen a full spectrum LED grow light, some (including this one) will look purple to the eye, making everything around the grow space seem purple. These lights are built to grow plants, but they are not the best for viewing them. If this spectrum bothers your eyes, have no fear; LED Shades will filter out the unwanted spectrum and will make it much easier to work in the grow room and see your plants with a natural color.
Growing with LED
There are a few considerations to be aware of when growing with LED. The biggest is increasing the temperature in the grow room. Typically, we recommend anywhere between 75-78 degrees for HID’s and 82-85 degrees for LED. The reason why is pretty simple: plants grow faster when they can transpire at an appropriate rate. HID’s have more thermal radiation so they will increase the temperature of the leaf surface over the ambient temperature of the grow room. LED’s are so efficient at delivering light that they don’t actively increase the leaf surface temps. You will find that growth rates are much better if you bring those temps up a bit. The perk here is that if you are using co2, your plants can utilize more of that precious investment since optimal temps for co2 uptake fall in the 82 to 86 degree range.
As mentioned earlier, introduce new plants carefully. Start with just the vegetative spectrum until your plants respond positively. Once they do, turn on all diodes and slowly move the light closer to the plants. Usually 12 to 24” will work with these lights; however some plants will perform better with more distance between light and canopy. Think about the natural environment of the specific plant you are growing. Are you working with full sun or partial shade plants? Adjust the light accordingly.
Mechanics of the AgroLED Dio-Watt
The light itself is made up of 3 watt diodes in 10 different colors. These diodes are powered by a series of drivers, and the unit is cooled by several axial fans that are mounted at the top of the unit so that the heat is drawn up and away from the unit’s components. Each diode emits light through a 90 degree optic lens that focuses the light onto the plants where it should be. The units can be powered by 120 or 240 volts, and each unit comes with a 7’ power cord. You may notice that the total wattage on each of these units falls short of the total diode wattage. For example, the 288 unit (96 diodes x 3watts) only uses 175 watts of power. You will see this across the board for most LED’s because it would not be ideal to power those diodes at 100%. The diodes will will last longer with the 60% driving force and your plants will get adequate light.
***NOTE*** The large 1440 unit contains 10x 12K bulbs that are not found in the smaller units.
The best way to determine what unit best suits your needs, we’ll list the footprint each unit will cover with a link to the diode chart.
Dio-Watt 288 – 175 watt – ideal coverage 2’x2’ – chart
Dio-Watt 432 – 265 watt – ideal coverage 2’x3’ – chart
Dio-Watt 720 – 450 watt – ideal coverage 3’x3’ – chart
Dio-Watt 1440 – 865 watt – ideal coverage 4’x4’ – chart
Below is a photo of 4 Thai Chile Peppers being grown in the Asheville store. The light could probably be moved a little closer to the plants, but we are seeing great growth with the light about 30 inches from the canopy.