Have i got enough light?

[Gorhad]

Thanks ColoradoHigh but its a PDF document?

Heres the link anyway

Specialty Applications
How can I evaluate the effect of different light sources on plant growth?

https://assets.sylvania.com/assets/documents/FAQ0017-0605.ed512ef3-36b1-47cb-b052-0f9ca74348ca.pdf

 

[David Bowman]

Can you output that document into one of the accepted formats using Adobe Acrobat Reader?

Never mind, it looks like Adobe Acrobat Reader can only output as PDF, Text or Word/Excel formats. Perhaps the full version of Adobe Acrobat can perform this function.

 

[netstatmen]

i think this is a great explanation (from Quazi)

PAR stands for photosynthetically active radiation.
In other words: the area of the spectrum of light (or color) where plants and light interact. I say interact, because there are two things to look at when you're talking about light and plants, how well chlorophyll a, chlorophyll b, and the carotenoids absorb the light that is coming in and the rate at which photosynthesis occurs relating to different spectrums or the "action spectrum."

Chlorophyll a absorbs red and dark-bluish light.

Chlorophyll b absorbs orangish and light-bluish light.

The carotenoids absorb the blues and purple which is towards the ultraviolet end of the spectrum where radiation can be harmful to cellular life at certain levels. As such, the carotenoids also help to protect the plant from this radiation.

Most other colors are reflected giving off the green tone that we are so familiar with.

 

[Gorhad]

Now we talking netstatmen so in my case should I get bigger wattage bulbs with same lumens and kelvins?

 

[Gorhad]

I don't want to burden you at all but is there anyway it could be explained in simple terms for us novice growers who want to learn and better their knowledge please. Take my setup as a guinea pig if you want. At least it would explain its not just lumens or qty of light sources its the PAR of the light sources that are a major factor too. In my case on a budget I opted for the lower wattage bulbs. Which in hindsight are not exactly correct due to their lower wattage

Thanks

 

[Gorhad]

Maybe this could then be added to the afore mentioned cfl tutorial

 

[netstatmen]

hey there mate!

i think this is what you are looking for:

*CFL's of 6500K spectrum (Used for vegging both: seedlings and clones) These lights glow white with a slight blue tint (is called cold white in stores i think, just make sure it is 6500K)

and

*CFL's of 2700K spectrum (Used for flowering) These lights glow yellow/orange (called warm white in stores like Home Depot)
just make sure you have enough watts for your growing area as i said before.


it would be better if you make a grow journal, that way you can receive close attention and advice through your whole grow, there are tons of excellent growers here and in my experience they all are expecting to help new growers like you and me.

i am currently under my first grow and find this extremely helpful, it would be awesome if you can visit my journal too:
Netstatmen's Soil Auto Red Poison LED Grow Light Journal - 2013

anyways, i would like to know how your grow turns out, and if you will be training your plants or how are you planning to grow?
this also helps as background info so you can receive more accurate advice

 

[Gorhad]

But what wattage would you suggest.?

 

[netstatmen]

But what wattage would you suggest.?

as i said, i'm no expert and personally have never grown with CFL's, but in order to tell you how many CFL's and what watts, we will first need to know your grow box dimensions, remember that you need to distribute the light, you don't want all your lights at the top allways, (that is why i asked you about your growing plans, LST, topping, fimming, or what kind of training will you do?)

this is very important to determine how many bulbs and where to place them, for example, lets say you need 400w total, so if you buy two bulbs (200w each) and put them above your plants, this will work good for a while, but if your plants grow like christmas tree (their natural way to grow), then you are not taking advantage of that light, and will traduce in lower yield.

the reason is because the main stem and upper leaves will receive all the light directly, shadowing the lower part of the plant, so the lower leaves will die.

So, if you will let your plants grow like christmas tree, you would prefer to buy several lower wattage CFL's (taking the example of the hypothetical 400w, you would need 4 CFL's of 100w each) to put some of them at the sides of the plant, so your plant can receive light in her lower leaves.


hope i explained myself (note that the above paragraph is just an example, i'm not saying that you need 400w total)

 

[Gorhad]

hello there, for optimum light, you should have 30 (as minimum) to 60 (max) watts per square foot.

Here is the formula:

Square footage (length × width) of your room x 20 (wattage)
= The watts needed

i use LED grow lights, never personally used cfl's but i think it is the same criteria.


(lumens are for humans, PAR is for plants)
hope this helps

My grow area is an odd shape, however if i measured it as a rectangle then i have 4 feet x 2 feet = 8 sq feet. I have a total CFL wattage of 318, therefore my watts/sq foot = 39.75 which is a tad over the minimum. Would that be just about sufficient?

Thanks

 

[netstatmen]

My grow area is an odd shape, however if i measured it as a rectangle then i have 4 feet x 2 feet = 8 sq feet. I have a total CFL wattage of 318, therefore my watts/sq foot = 39.75 which is a tad over the minimum. Would that be just about sufficient?

Thanks

yes my friend, that will do and it is sufficient, but for best yield i would go 50w per sq foot as i think is the optimum, so i would add a few more CFL's, that way you will get bigger yield as you unleash the full potential of your plants. (be careful not to over light with more wattage than recommended)

cheers

 

[Gorhad]

Just one more question although the grow area is 4 x 2 = 8 sq feet. The actual canopy they are in is 2 feet x 18 inches = 3 sq feet under the reflector hood. Could that not be used at the grow area figure rather than the whole cupboard its sitting in. Im asking this because im running out of space to mount extra bulbs on the reflector hood lol

 

[closetorganic]

I would say you only should be concerned for the space you have plants in and you are probably good.I have seen and been interested in side lighting others have done that helps.I think its the light penetration that matters too.I mean if you bush out your plants there could be alot of the plant out of light penetration where side light will help but I feel most help would come from training your plants with LST or scrog style having more buds filling up you canopy all getting equal light and giving you more yield

 

[netstatmen]

Just one more question although the grow area is 4 x 2 = 8 sq feet. The actual canopy they are in is 2 feet x 18 inches = 3 sq feet under the reflector hood. Could that not be used at the grow area figure rather than the whole cupboard its sitting in. Im asking this because im running out of space to mount extra bulbs on the reflector hood lol

hey there friend, well i think that depends on how much you want them to grow, i have a friend that grew in a drawer of his computer desk, so he had a healthy but very small plant, and he actually did get buds (very small harvest too).

so i would take as "grow area" the whole area between your reflective walls, remember that i told you about light penetration in lower leaves, so you should place some CFL's in sides when the plant requires it.

for example, here is a pic of my grow area:

also if you don't have enough space for several low-wattage CFL's, you could try a little bigger ones in order to meet the 50watt per square foot? (i guess you can mix bigger CFL's with what you already have) this is just a thought

 

[Gorhad]

Thanks everyone this forum and all you guys rock. Love it

 

[Lady Cannafan]

......................

also if you don't have enough space for several low-wattage CFL's, you could try a little bigger ones in order to meet the 50watt per square foot? (i guess you can mix bigger CFL's with what you already have) this is just a thought

I do that with my grow, a mix of larger and small cfl's. It looks funky, but hey...who cares about the looks of it. LOL

 

[Lady Cannafan]

If you are handy at all, check out this CFL light tutorial.
Scroll to post #19 and the instructions are there with pictures.
The beauty of this design is that you can make it oblong or square to fit what you need, and you get the complete benefit of the side lighting strength of the CFL bulbs. I have made one, and plan to make two more.

CFL Light Tutorial

Here's my first one:

Edit: I wanted to add that I can see a definitive difference in the flowering with this style fixture. I have two scrog areas, one with the above PVC style CFL and one with the style like yours. They seem to be fatter and healthier looking green to me under the PVC CFL fixture.