light spread of CFLs help pls

I am about to grow under CFLs was wondering how far the light spreads with CFLs.

As I have to keep the CFL close to the plants do I need the bulbs housed in a reflector that covers the whole area of my garden or will the light spread at all. I have an area 18" x 3' and from what i work out 1 x 125w cfl would give enough light for vegatative growth but this in a single bulb reflector wouldn't get near to covering the area of the grow so do I need to use more bulbs and a bigger reflector or will the light spread outwards when kept as close as an inch from the tops?

ta for looking

I would get some more 26w cfls for additional light. For vegging....dont put your cfls closer than 3-4" from your leaves.......when flowering put them within an inch or two of the buds and put some fucking wind power all over those lights!

Hi there,
how many plants are you planning on growing? i'm using cfl's aswell you shouldn't really need a reflector just keep the bulb about an inch or 2 above the plant, mine seem to be growing quite well even though i don't have a reflector. I'm using a 25watt and an 18watt cfl on each plant and the plants seem to be doing well for 2 weeks. just keep your bulbs an inch or 2 above your plant/plants. Get a few more bulbs and that should do the trick hope this helped.

• Watts: 18w
• Lumens: 1200

• Watts: 25w
• Lumens: 1700

so i think my plants are getting roughly 2900 lumen each


Dunno if you wanna try this too but my plants love it (this is what the tubes in my pics are for)

Pliskin095 said:

Hi all,
i wasn't sure if someone has already written a thread about home made C02 so here it goes, to make home made C02 you will need :- Bakers yeast, Sugar and tap water.
To begin you can use an empty drinks bottle (i use a 1.5 litre bottle), fill it with 3/4 water and 1/4 Bakers yeast (powdered or solid) i use solid as you can get it from most bakeries free, then add roughly 250g of sugar and screw the lid back on (its important that the lid is air tight) and leave it for about half an hour, once it has been left alone for half an hour go and give it a shake and hopefully you should be able to see bubbles in the bottle.
Remove the lid and make a hole in the centre of it (approx 1-1.5 cm) and screw the lid back on, there you go you now have home-made C02 just place the bottle below you plant pots, after 7-10 days the process will have to be repeated from scratch.
Hope some will find this useful
Peace out
Pliskin095

Click to expand...

those higher watt ratings are just a comparison to incandecent bulbs, nothing more, it does not mean you are getting that mant watts per say.. you need to pay more attention to lumens, how many you get PER watt of electricity used, and the spectrum.

if the reflector wont cover your area properly you can..

1. make your own, or maybe bend the wings out on yours, depending on what reflector you have.

2. take the reflector off, cover your walls and cieling with mylar or white paint.

3. get another one. the more the merrier unless your dealing with fresh cut clones.

you can usually get cfls about an inch, test for heat, if it doesnt burn you, it shouldnt burn your plants. and vice versa.

Ta!

There is not much need for a reflector then if lining with mylar?

I'm not at that stage yet but what sort of light will I be looking to give fresh cut clones?

floro tubes do well, at about 4 inches from, or cfls at 5 or maybe more inches, the reason is you dont want this clone to use up alot of light and nuts while its rooting. if you do they will take longer and maybe die, low light uses less nutrients, and less moisture, all of which your plant cannot get from its roots, only from itself, this is why you want to mist them and keep high humidity.

So it could be worth using a lower watt CFL for rooting clones then, is there a suggested amount of lumen for rooting clones?

Is it acceptable to not use a reflector if walls and ceiling are lined with mylar or would it always pay to use a reflector?

i would say acceptable as long as all walls and cieling is lined.

a wise man once said (Garden Knowm) 1 42 watt cfl was good about 6 inches away from my 5 clones.... and now you KNOWM of course once rooted they will need better.

Ta Russ

One more thing, what sort of sheet would I use to make a reflector, the retailed ones seem to be really shiney like in a sunbed (polished steel?), Im not sure what to use to make one?

im going to the home depot this weekend and am going to buy 3 8' floros 4 bulbs a piece can any one tell me if that will be good enough?

I made a cardboard reflector, with 4 42 watt cfls, and i am going to line it with mylar.

here it is without mylar

Here is some insider information that should help!
(this is an exert from the section on lighting in my book)

Light Intensity
Light intensity diminishes the further it has to travel. This is the same for HID, CFL or your normal household lamp.
If you hold a light meter up close to any lamp and then slowly lower the meter, even a few inches, you will see the light measurement reduces dramatically.
(If you can borrow, beg, steal or get access to a light meter please try this ~ you will be extremely surprised at the rate at which the light intensity reduces over a short distance)

Light from an HID or HPS lamp reduces by half for every foot it is away from the plants.

So if your lamps are 2’ or 3’ above your plants much of the light is wasted. The problem with HID lamps is they are so hot you cannot place them close to your plants and much of the light, and your money, is wasted.

One benefit of using high-out put CFL’s is that they do not generate as much heat and can be kept almost on top of the plants producing the exact 100% PAR light, with no loss of intensity.
(So if you position these new lamps close to the leaves you get the benefit of 100% PAR light in the correct 400nw to 700nw range, giving the plant the correct light colors and light quality.)

Growing With CFLs
CFLs can be used to grow seeds and to propagate cuttings.
They can also be used as the main lighting system for plants in the vegetative and flowering stages.
(The secret to growing with CFLs is to position your lamp or reflector just an inch or two above your plants.)
Positioning these new compact lights directly above the plants maintains light intensity, no lumens are lost and the PAR / Spectrum is 100%, which is like natural sunlight.
The plants get all the lumens they need with the light being in the correct spectrum.
CFLs are available in 125w and 200w models that are avaible in:
> Natural Daylight 6400k (kelvin) (Great for vegetative growth)
> Warm (Red) 2700k (kelvin) (Great for FLowering)

Many growers use these lamps as a supplement to ‘hang’ by the side or in between plants when flowering.
They can be used with HPS lamps, as a supplement or by themselves.
We use them 100% and no longer use HPS lamps.

Some red light in the vegetative light mix is also recommended, as is a little white / blue light in the flowering mix.
With different combinations of red and white lamps growers can obtain the ideal lumen output and spectrum required for excellent results in all stages of growing.
125w and 200w CFLs provide 100% PAR, which is such an important factor.

It is important to be able to calculate the PAR values obtained from your grow lights and how much light your plants need to give maximum yield.
If you are using HID / HPS lamps you should contact your supplier and ask them about PAR output, it is important that you know this as well as lumen output.

Mile High said:

(this is an exert from the section on lighting in my book)



Light Intensity
Light intensity diminishes the further it has to travel. This is the same for HID, CFL or your normal household lamp.
If you hold a light meter up close to any lamp and then slowly lower the meter, even a few inches, you will see the light measurement reduces dramatically.
.

Click to expand...

Thanks for this, what book is this?

I appreciate how quickely light disapates as you move the lamp further away upward I was kind of wondering how it works going sideways, the same then I guess?

good info guys, especially u Mile High...I've been reading and trying to find out more about growing with cfl's and if they could be used to grow through the plant life and produce great results...Mile High, if i read that right, the book says they used cfl's all the way and not hps? so it must be possible to use them and produce good yeild...?

You can check out the "Aerogarden" threads. The AG is a self-contained unit which has a small hydro reservior and has two 24w CFL lights. It's one of those things you see on late-night infomercials and sharper image catalogs. Anyway, my plants are doing great with it! I just posted an update after 45 days of flowering with some pics...might be of some interest.

I just purchased some additional CFL lighting (two of those small reflectors with the "clamp" holders )..so that should help the next time around!


Here is a link to the post
https://www.rollitup.org/hydroponics-aeroponics/5041-aerogarden-update-new-post.html

wow this is good info.....i was wondering if u could grow with cfls thru the entire grow......im learning so much from this site......i think i might just have to join u guys on ur voyage of enlighting ppl that growing is the best and only way

More thoughts on lighting

(A comment on your space)
I think if you are growing in a 18" x 36" grow space you could use 2 125w CFLs successfully.

(I recommend you use the Natural Light type (6400k) for vegetative growth
and the Red Spectrum type 2700k for flowering)
So you will need 4 light bulbs total and you will need to change bulbs when you start budding.

Put them in a 16" reflector and center the reflectors across the 18" width of your room.
Run the reflectors length wise in your grow room.
(Butt the bases together in the center with the bulbs pointing length wise towards the ends)
Put mylar on your walls.
(we use tek-foil and we cover walls, floor and ceiling)


Answer:
The book is:
In the Beginning
"A Guide to Growing it Great"

It is still going through final editing so don't bother trying to find it on the book shelves yet. We hope to have it out by fall.

Does this also apply to the spiral CFL's found at HD and Lowes? They are lower wattage (27watt-45watt), but if you have enough they should be able to produce a good yield no? Would like more info if possible!!

Shit!
I just errased the reply I wrote! Anyway I have to log off for a while. I'll redo my reply later.