how much light is too much?

[justcurios]

is it possible to have too much light in a veg closet? i have 2 high powered flouresent lights and a 100 watt hps vented with remote ballast. temps stay about 80-85. the room is only like 2 ft. x 3.5 ft. my buddie read that too much light can mutate plants. possibly stress them out, maybe herm out. or just plain burn up. the soil drys out really fast. any thoughts would be helpful. thanks- stay high

[humble1]

i'm sure someone behind me will drop the mad science on this, but the basics are simple: plants can only use so much light. once a certain PAR is reached (although most figures measure in lumens or watts/ft squared) the extra light is either reflected off of the leaf surface or absorbed as heat, not photosynthesized. too much heat in the leaf itself is bad news. i would choose one or the other (floro or hps) rather than both. veg really doesn't require too much light and in such a small spot either would be fine as long as the light source is close enough to the canopy to be effective.

[Bongojaz]

everything i've read suggests, you can't have too much light. as long as heat isn't an issue, there should be no problem. of course, you don't want so much light that your power bill looks like you're powering the whole block....

[Green Supreme]

Safe power consumption would vary from area to area. As far as useful light goes, cannabis grow outdoors. You can't compete with the sun no matter how many lights. Be safe. Peace GS

[justcurios]

so really as long as heat is not an issue, lots of light is ok. it makes sense that too much could burn the leaves. then again like green supreme said its hard to compete with the sun. i have the small hps with flouros to try and give a more even spectrum of light. my theory is to make an easier transition to the 1000 watt hps at flowering. like i say i have read articles that state too much light is bad. i think it was in a fairly recent edition of high times. some garden of zen article. thank you all for the input.

[outdoordreams]

Just curious, using different lights in different spectrums is a good idea!

Correct me if IM wrong but.....
?With indica plants the more light you use the denser the plants will be!

If you increase light intensity, you may want to increase the CO2 level in the grow room!

[gforce]

i think the only problem you may have is if the bulbs get too close to the leaves... also, lay something plastic over the soil to hold in the moisture... i always use at least 5 gallon pots to be sure there is enough reserve moisture in case i space it out

[smokinbasser]

If you have more measurable lumens in the closet than the sun can provide outdoors you might be approaching max light output.

[nuggdigger]

[QUOTE]Plants and Carbon Dioxide

People laughed when it was claimed that playing music to plants made them grow better. It really did because the sound vibrations actually strengthen the stem fibres, shorten the internode length, and cause stress growth reactions from the plants.

Then people laughed when it was claimed that singing to plants made them grow better. However, it is true. The CO2 from human breath actually makes plants grow faster. If you and a few gardeners stay in the indoor garden area during the light period, the plants would do very well.

It is thought that the massive plants that developed millions of years ago had
lived an environment with much more carbon dioxide in it. In their
evolution, the plants still maintained the capacity to use much more carbon dioxide than the world has now.

Luckily in the smoggy cities, the CO2 level can be as high as 500 PPM, and by just having a good circulating fan, the plants should have enough CO2 for a medium-light indoor garden.

A high-light indoor garden with the carbon dioxide amount increased from an ambient level of 300 PPM to a high level of 2,000 PPM can nearly double plant growth.


Why All Plants Need CO2

The dry matter in a plant is 90% carbon, hydrogen, and oxygen. All the
carbon has to come from the carbon dioxide (C02) in the air.

CO2 molecules are only necessary during the light times. Plants do not need CO2 in the dark period, and in fact plants breathe out CO2 all the time, just as humans do. The slight difference is that in the light period, leaves use up their own CO2 to make sugars and so appear to breathe out only oxygen in the daytime.

The more light available to a plant, the more CO2 it needs for photosynthesis. Experiments have shown that during photosynthesis, it takes about 1 a photons to make enough electrons to create sufficient energy to split one CO2 molecule into carbon (c) and oxygen (02) atoms and form a sugar. There are trillions of photons striking the plant leaves, so a grower must provide enough CO2 or else the photons will just bounce off the leaves without doing much.

A plant in full Sunlight (about 5,000 lumens per square foot) could process about 2,000 PPM of CO2 if it was made available in a greenhouse. Outdoor CO2 is nowhere near that. Indoor gardens with the light level at 3,000 lumens per square foot need about 1,500 PPM of CO2 for the limited light. With the level at 1,000 lumens per square foot, only about 300 PPM of CO2 is required - which is less than ambient air (city air normally has 400 PPM of CO2), The lower the CO2 level, the more the air has to be kept moving past the leaves.

Remember that it is the PAR value (not lumens) that indicates the plants' use of CO2 because the light that the leaves cannot sense is totally wasted and does not go down the photon funnel to be used for splitting CO2 into sugar.

How Much Carbon Dioxide Can Your Indoor Garden Use?
Experiments have shown that plants can handle up to 10,000 PPM of CO2 with no ill effects. At very high light densities, indoor plants have a maximum CO2 uptake of just over 2,000 PPM.

Light intensity increases with closer distance, so the CO2 level around plants needs to be increased respectively:

Lights Distances CO2 Needed for
from Plants Sugar Production
HID Lamps 4ft (120 cm) * Ambient
3 ft (90 cm) 400 PPM
2ft (60 cm) 1,000 PPM
1 ft (30 cm) 2,000 PPM

This is with maintaining all plant resources at MAXIMUM and at a temperature NOT EXCEEDING 30

[nuggdigger]

C02 Necessary For Light Usage

[nuggdigger]

The photon side of the carbon-fixing reaction is not temperature dependent, but the non-photon reaction of carbon fixing in most plants increases with the temperature up to about 86 F (30C), after which it starts to slow down. During the intense photosynthesis, the leaves have to store excess starch in their cells. In the dark, they convert the starch and sugar to ship the energy to the rest of the plant, especially the roots. In supercharged plants, the leaves and their petioles(leaf stems), as well as the plant branches, become very important storage places as do the roots which grow into enormous bundles because the leaves are producing energy at many times the natural growth.
Would more light make bigger and better plants or more fruit and flowers? Her are some answers. The Sun has a very high density of 5,000 lumens per square foot. This means that there are lots of photons striking every square foot of leave surface. In a good sunny summer, the plants and fruits are noticeably better and more abundant.
A billion years of plant evolution has made most plant leaves do their best light to energy conversion with sunlight between 3,000-4,000 lumens per square foot. However, because of shading and dense foliage, only the top and outer leaves get this much light intensity during a part of the day. the rest of the plant is in some form of indirect light or in shadow most of the time. If the overall light density around the plant is increased to 10,000 lumens, a large percentage of its inner leaves 'feels' 3,000-4,000 lumens, due to greater light penetration. Now the plant can in fact double or triple its energy conversion, and amazing things happen. One should not overpower any specific parts of the plant by putting them too close to the light, as this destroys the chlorophyll pigments. Leaves have an internal regulating system that increases with lower light density and starts to shut off energy production in higher light density.


NOTE: this particular post I was unable to obtain off the Internet. I did however pay for the book and am sharing the info purely for educational purposes. I hope that the Graham Reinders considers this a form of free advertising and promo, as How to Supercharge your Garden is after all a fantastical informative readable book that I would recommend to anyone.

thank you

[The Cannarchist]

I met him the other day,Graham Reinders.Interesting guy.He is now into supercharged organic teas,beneficial microbes and fungii.......I wonder how many of those books he sold Nugg...because he lives in the Tropics now,lucky guy!

[justcurios]

thanks for the info nug, good stuff.