LED Grow Lights - Why Swap in Summer?

Summer’s the most challenging season for indoor growers.

Temperatures increase and plants can struggle. Getting a good yield can be harder than ever! To survive, you need LED grow lights. Here’s why.

We ran an LED test to find out if LEDs are really cooler when you get the wattage right.

In a 1.2m x 1.2m tent, we found that 2 x Telos 0008s (480W) were:

• 3 o C cooler than a 600W HPS
• 1 o C cooler than a 315W CDMs

Interestingly, the temperature only got 1oC hotter when we used 2 x Telos LEDs instead of 1 x Telos LED.

In summer, plants in hot grow rooms transpire very quickly. This is to try and cool themselves down and regulate their leaf surface temperatures.

To replace the water lost, plants take up more water via roots, and fewer nutrients. At best, this slows growth.

As plants draw up more and more water through roots, the nutrient strength in your pots, tank or system quickly climbs way too high. This can cause toxicity.

To offset this with HID lights, you need to reduce your nutrient strength which can impact your yield.

To prevent this without losing yield, switch to LEDs. They put out less radiant heat than HPS & CDM lamps. With a lower temperature, your humidity stays high and plants don’t lose too much water.

Since plants don’t over-transpire with LED lights, they can cope with a higher nutrient strength.

Also, plants may actually be getting more PAR light. The PPFD is higher from 2x Telos LEDs than a single 600W light. This means their nutritional needs stay the same or increase!

As a result, you can push your nutrient strength. Since plants lose less water, you can also reduce your irrigation frequency.

Adding CO2 increases the rate of photosynthesis and can increase your yield by up to 30%! It can even reduce the flowering cycle by up to 3 days. But that’s only if you can get the CO2 in contact with your plants for long enough.

With LEDs, your air temperature isn’t as high, so you extract less air. This means any CO2 you add has time to be used by plants before it’s sucked out of your tent by fans.

In summer, you normally extract more air to combat heat. If you switch to LED lights, you won’t have to extract anywhere near as much. As a result, any CO2 you add will be hanging around plants for a lot longer than it otherwise would.

With a lower temperature, fans don’t have to work as hard to remove heat. EC fans (and AC fans slowed with a Control Freak Dynamic Frequency Controller) are much quieter at slower speeds. Telos LED lights are also cooled passively - there's no extra fan in the unit to make noise.

With Telos LED lights, running costs significantly drop.

You get more PAR light from a lower wattage if using Telos LEDS over HPS lights. This means you’re using less energy to get more plant usable light.

Add to this the fact you don’t need to replace anything for 10 years, and the LED pays for itself.