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Martin, Engineer
Category: General
Satisfied Customers: 4932
Experience:  i'm 41 and i never stopped studying and experimenting
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Do you have a horticultural expert I have a question about

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Customer: replied 5 years ago.
How important is infra-red light in the conversion of vegetative growth of plants to flowering? This is with particular reference to Marijuana (please note I am legally allowed to grow as licenced by the Government of Canada)
When growing marijuana indoors under artificial light, will infra-red stimulate bud development & at what time of day(end/beginning) & for how long?
Hello. Yes infra-red is important for flowering and would help for the bud.

I don't know if that particular plant know when to flower by the length of the days (that would require predominant infra-red at the sunrise and sunset, not a big intensity but just a predominance) or by simple increased intensity on a normal distribution at noon.

You should not use too much IR inside as without wind it may burn the leafs even if the watering is controlled. Another thing that may happen with too much IR is long thin stems that won't be able to aliment the bud properly.
Customer: replied 5 years ago.
Sorry for delay--got side-tracked! Your answer was very helpful. Just need a little follow up. If the I.R. is to be predominant, should the main lights be dimmed or even off when the I.R. lamp is on? Secondly, to further avoid burning, would it be better to reflect the I.R. indirectly off a white surface ( e.g. a wall or ceiling )? Would that be effective? Thanks in advance. I'm Martin too!
For the predominence, normal light should always be present at the same time. The simpler would be to have normal light with fluorescent tube while providing the IR with IR light bulb driven with triac (those allow for a variable % of the intensity by allowing only a % of the 60 hz cycle). You can then control the gate of the triac with a computer, microcontroler or commercial systems to have the right kind of day lenght simulation that you want.

To not have burning from IR, indirect lighting would do just the same as just using a less powerfull IR bulb. IR does not do a spot like with a fresnel lense, its kind of diffuse already. It should be far enough of the plant, a slight wind from a fan would help and maintaining a good level of humidity. Plant that got exposed as soon as getting out of the seed with IR will have less chance to burn from it latter.
Customer: replied 5 years ago.
This is great information, but I am not at all familiar with " triac ". Could you please expand. Thanks. from Martin to Martin.
A triac is a component of a efficient kind of light dimmer. Those circuit can be controlled, it always depend on how fancy you want your system :)

To keep it simple you may just put an on-off timer on the IR source and if it work well you may not have to use a fancy progressive system with a gradient of light in the day. To give something similar to a progression in the day you could put 2 or 3 IR sources that are ON at different period in the day (when the 3 are ON at the same time it give more IR, when only just one it would give less).
Martin, Engineer
Category: General
Satisfied Customers: 4932
Experience: i'm 41 and i never stopped studying and experimenting
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