Help with lighting distance

I started my first grow with two 42 watt 2700 lumens cfl's, and I've read to keep lights 12 inches away. My friend told me to keep them four to five inches away. So I did that and checked them this morning one of them was withered to shit that one was closest to the lights and the others looked withered a little bit, but not too bad. How far should i keep the bulbs away from the plants?

I think the 2700 are for flowering? I dont use CFL's so I may be wrong.

Boneman said:

I think the 2700 are for flowering? I dont use CFL's so I may be wrong.

Click to expand...

2700 bulbs are best used for flowing, for vegging your better off using lights on the other end of the spectrum (such as 5600K bulbs). It sounds like your starting a decent number of plants so I would be sure to pick up at least four more bulbs. Your problem could be lack of light.

As far as distance goes, you want the lights as close as possible without burning the plants, Normally that means 1-2 inches. A good way to tell is to put your hand in front of the bulb and slowly move it away until the heat is comfortable on your palm. However if the lights are to far away the plants will stretch upwards towards them and become stringy and weak. Experience will help you find a balance but if you post some pics I might be able to offer more help.

Smokinwithewoodlandfairie said:

I started my first grow with two 42 watt 2700 lumens cfl's, and I've read to keep lights 12 inches away. My friend told me to keep them four to five inches away. So I did that and checked them this morning one of them was withered to shit that one was closest to the lights and the others looked withered a little bit, but not too bad. How far should i keep the bulbs away from the plants?

Click to expand...

were they properly waterd and hows the air flow

how big are they

they are gettin good air flow and watering about every other day they have been growing for about a week and half

Seems like they might need more water. The heat mixed with how small the cups are could be drying them out. Also move the lights closer.

Just noticed there in a cupboard. Do you have any way for air to get into it when its closed?

newb19547 said:

Seems like they might need more water. The heat mixed with how small the cups are could be drying them out. Also move the lights closer.

Click to expand...

how close does it need to be and do i need to get different lights bc they are 2700 lumens they aren't right for veg growth

Smokinwithewoodlandfairie said:

how close does it need to be and do i need to get different lights bc they are 2700 lumens they aren't right for veg growth

Click to expand...

I'd say keep them about 4-5 inches away. You don't "need" better lights, but you definitely want them. The 2700k will work, but I'd say get 6 or so more (6500k) or one or two Big 100+ CFLs for now. You want even more than that if possible

ya theres a fan in there and also one on top blowing through a couple of holes but when you say 2700 flower 6500 veg do i need different lights that put out 6500 or more 2700 lights

Smokinwithewoodlandfairie said:

ya theres a fan in there and also one on top blowing through a couple of holes but when you say 2700 flower 6500 veg do i need different lights that put out 6500 or more 2700 lights

Click to expand...

6500k is the kelvin temp of the light bulb which is more in the blue color spectrum, the plant need more blue during the veg cycle. . so yes you would need different cfls they are around the same price, ive seen them at lowes, walmart, homedepot. look for these names soft white or warm white=2700k-3500k red spectrum. . bright white or daylight = 5000k-6500k blue spectrum.

Twistyman said:

If its too hot for back of hand ..it is for plant..... with the big CFL's you have to play to find the sweet spot.. until adjust and watch carefully for distress...

Bonemans (hey weed), right 2700 flower.. 6500 veg..

I'd get them into more soil too.. planted right up to bottom leaves.... Luck

Click to expand...

Hey bro. You are wise to get the lights as close as possible w/o burning them. You have to move it in inch by inch, 1 day at a time. Imagine if the August sun and heat came up in April. We would all be eating a lot of dried food any way. I have done the same thing. Mimicking nature is mostly what it is about.

you can veg fine with 2700 its not like they wont grow its just better to have a little blue light(6500k) and get some y spliters so you can put 2 bulbs in each lamp

they sell them at home-depot for $1.69(ea)

heres my rig the y-spliters is the socket screwed in the origonal socket

I know I am sounding like a parrot in here because it has been said before but...

Top cups look pretty dry. (is there an air current cycling through the cups? could cause them to dry out too fast all the time)


Anyways on to the K issue. You can veg with 2700's just fine, people veg with hps @ 2200k. just 2700k is not as productive as 5300k+ but works none the less. So if its what ya got use it

A quick question about the plants. Were all the plants under the lights when they were lowered? If so and those did wilt from the heat the rest are fine, drop it down

Distance should always be kept as close as possible. 2" from plants and you should never have a problem. But for veg I guess to be honest is put them where they work for ya, farther away less usable light gets to the plant though.

If you look at this chart for MH and think of what your actually loosing per inch with cfl you will get as close as possible. Just fyi cfl's that are 12"+ away from a plant are to be considered not providing your plant anything (in flowering that is the case at least)

Anyways check out the lums lost per " with an HID now think about the crappy lums kicked out from a cfl and OMG its time to get close close

(Also in case anyone wonders I found this on google images but couldn't find anything for cfl. Def would be a nice handy quick ref for people if anyone has the data )


Anyways lookin good. The amount of dirt in those cups is def gotta be commin close to not being able to sustain them nice lookin lil ones though. with the fan, heat & a young thriving root system that lil o dirts gonna go bone dry fast.

Def nice looking plants though. Best of luck. Hope i havent said anything offensive, if so just say so and ill fix

This one is under a single 100w cfl

This is my mother under 4x 26w 5300k's.

12" is definitely too far. I used 6500k lights placed no more than 3" away, 24/7 through the seedling and veg stage. Then switched to a mix of 6500k and 2700k on a 12/12hour schedule with the lamps 1" away from buds for flowering. While every precaution should be made, the truth is you are going to burn some leaves. Other variables aside, the MJ plant is hearty and will tolerate it.

Attached are some pics at day 51 and 55, just to give you an idea of proximity.