Determining Optimum HID Light Height

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Weedguru Higher
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Determining Optimum HID Light Height

Post by Weedguru Higher »

How To Determine Optimum Light Height for Growing Marijuana
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Hanging lights is one of the biggest challenges for a new and experienced marijuana grower. Starting from marijuana seed requires lights to be hung from a fairly precise distance.

But don't worry.

By paying attention to your marijuana plants and these tips you'll be able to determine the best height for growing your marijuana seeds.

Be prepared to adjust your lights based on the marijuana plants response.

It is extremely important for indoor marijuana growers to get their light source as close as possible to their cannabis plants. The amount of light your marijuana plant receives is directly related to it's yield and vegetative growth patterns.

Marijuana plants may stretch if the light source is too far from them. While marijuana plants that are too close to lights may get burned from heat.

The problem: Indoor lamps give off large amounts of heat, to such a degree that they could cause damage to the marijuana plant if put too close.

There is an optimum distance/height between your cannabis plants and your light source. This distance fully illuminates the whole canopy with direct light from the source, but is as close as possible to the marijuana plants for maximum growth.

Lets refer to this as OLH for Optimum Light Height.

First move your light to the OLH and see what it does to your marijuana plants.

If they have no problem, then you're fine.

The first problem marijuana growers will encounter is that the OLH is burning their cannabis plants.

Try venting or circulating air directly around your light.

Attach a light hood with a direct exhaust system. Using a venting system to push heat away from the light and the marijuana plants is the best solution. Circulate heat away from the light and out the grow room while drawing cool air from outside the grow room.

If the marijuana plants still seemed affected by the heat, then you must add glass to your light hood. Glass will absorb/reflect/filter some of the light energy being emitted by the lamp.

Almost all glass offered today for insertion in air-cooled lamp hoods is tempered glass, which is regular glass with low amounts of impurities.

You should periodically inspect and clean your light hood and bulbs, especially after foliar feeding or underleaf spraying for insects. The dust and dirt that collects will definitely decrease reflectivity.

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A simple method of testing for temperature is to use the back of your hand; if its too hot for your hand, its too hot for your marijuana plants.

Good ventilation is the key to getting your light closer to your marijuana plants.

Recommended typical OLH distances:
400w HPS: 1 foot
600w HPS: 1.5 foot
1000w HPS: 2 foot ... eight.html


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