T5HO Grow Lights – The Benefits

Are T5HO Grow Lights only for starting seeds and cuttings?

First you have to know some things about light in general and photosynthesis. Plants uses light as a energy source to convert carbon dioxide( CO2) into organic compounds as carbohydrates like sugar or starch, (food). This is complicated but the bottom line is that 95% of the nutrients comes from Photosynthesis converting H2O in the air, sounds crazy but look it up. Think about it as if you drink a glass of vitamins and just stand in the sun to get all the nourishment you need. That of course means that the amount of light is crucial to the development of a plant. But not only the intensity of the light is important, the quality of the light (PAR) is also vital.

Light as we see it is white, but it is composed of the colors of the rainbow. Plants “see” the whole spectrum except green which they reflect, but most wavelengths are not useful for photosynthesis actually only 450nm(Blue or 6500K) and 660(Red or 2700K) nm are important, the blue propagates the foliage growth and red the flowering. I will soon come to the benefits of T5HO Fluorescent as Grow-Lights for Growing Herbs Indoor, or for that matter any light loving plant or flower.

There is a lot of talk about “Lumen”, “PAR”, “PUR”, and I will not go to deeply into that today but just explain what some of them mean.

Lumen: The standard measure of the strength of the light.

Kelvin: The standard measure of the wavelength of light expressed in millions of a meter nm.

PAR: The standard measure that quantifies the energy available for photosynthesis in the light.

PUR: The standard measure that quantifies the photosynthetic useful radiation.

So I’ll move on to show why I think the T5HO Grow- Lights are superior to High Intensity Discharge (HID) systems as High Pressure Sodium (HPS) which is the most favored system by Indoor Growers because of their raw power.

The Lumen.

The most important thing about light, is to understand that it diminishes rapidly the further away it is from the target. Now, as I’m sure you know, HPS systems output a huge amount of heat and that means they cannot be used particularly close to the canopy for fear of burning. A 400w HPS system would need to be about 2 ft from the plant tops. So if a 400w system outputs 53,000 lumen at the source, it’s represented as 53,000 lumen at a distance of 1 foot from the target. The Inverse square law is light intensity divided by distance squared. So for a system outputting 53,000 lumen we now know the output will be 53,000 lumen divided by 2 ft squared (53,000/2×2) which is 13,250 lumen at the plant canopy.

By experience I know that 2 ft is not enough if you don’t have some heavy duty ventilation, so lets say 3 ft and do the math .53,000 lumen at 3 foot is (53,000/3×3) 5,888 lumen, so this 53.000 lumen bulb will only deliver 6.000 lumen at a practical distance.

A 2 ft 24w T5HO delivers 2000 lumen at the source. A common rig has 4-6 2 ft bulbs, mine has 6, so that makes 12.000 lumen and as they emit no heat they can be placed as close as 1-2” to the canopy with no loss of strength. A rig with 6 4 ft 54w bulbs will deliver 30.000 lumen at the source and the loss of lumen over the life expectancy of 10.000 hours is only 5%.

The PAR and PUR.

As I mentioned earlier plants use principally 2 wavelengths, 450nm and 660nm. If you look at the diagrams you will see that the HPS (left) emits practically no radiation in the 450nm range whereas the T5HO Fluorescent has a peek both in the blue and red spectrum. In the T5HO diagram to the right the yellow line represents the PUR or useful radiation, the white line the PAR or the energy emitted by theT5HO and the green what the human eye perceives.

T5HO spectrum

The Benefits.

So what are the benefits of using T5HO Fluorescent Grow Lights when Growing Herbs Indoor whether in a Grow Tent or Basement Garden? T5HO bulbs provide the ideal spectrum for plant growth.

The minimal heat does not require expensive ventilation systems and can be placed 1”-2” above the plant canopy which maximizes photosynthetic response. The energy saving benefits are huge, a 400w HPS system consumes 430w and the 2 ft T5HO system whit 6 bulbs in the example 144w while emitting the double light energy.

Energy consuming ventilation is not needed. Each unit is self ballasted, does not flicker, is noiseless and weights only 100 grams. You can connect as many as you need in a daisy chain or place them singly where they are most needed.

Some think that T5HO Fluorescent Grow Lights are only for starting seeds and cuttings and not for flowering and full term growth, but that depends only on the Light Period, if your bulb is 2700 or 6000 kelvin is not as important as the Light Period. For flowering/fruiting it should be set for 12h day/12h night, for the growing stage of a young plant when you want it to develop a canopy 18/6 or even 24 hours of light is vital.

So look out for the new T5HO Grow Lights that are now available. Look for them HERE

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