Question about CFL's and CFL growing!

[robbye]

I am currently growing a couple plants under CFL lighting(1 white siberian and 1 pineapple chunk), and I remember reading that CFL's should be kept within a few inches of the plants or else the plants will stretch and not get enough light,

However I have seen several posts where people have their CFL's secured at the top of the grow space, often a foot or more away from the canopy layer of the plants.

So my first question is, are these people doing it wrong or can I space my CFL's further away from my plants? Cause my plants have gotten burned in a couple spots where I didn't move the lights quick enough.

My second question is, When the plant starts to get bigger, should the light bulbs be above the plant, or all around it, or does it even make a difference? My plants are a week into flowering and one of them is a bushy beast. should I surround it with light bulbs or just leave it as it is?

And lastly I was wondering if trimming would be a good thing for me to do. The bushier plant has lots of tiny, less developed branches that just look scrawny. should I trim some leaves to allow more light penetration? And how do I tell which ones to trim?

Thanks for looking at my post and any help would be greatly appreciated!

 

[MrBosco]

I've been reading up on this topic for some time now researching a grow box setup. If a plant receives insufficient light it will stretch towards whatever light source is available. The less sufficient the light the more pronounced the stretch. In nature a plant that is receiving insufficient light is one that is shaded, probably by other plants, so it will grow upwards towards whatever patch of sky the plant can 'see' in an effort to break through the leaf canopy and compete for whatever light is available. So in answer to your first question, the more light you have projected onto the plant the less pronounced the stretch will be - thus the more CFL wattage you run the further the bulbs can be from the plant initially without stretch problems.

If you run bare bulbs without reflectors of any kind then you will need to place the bulbs much closer to get good results. Those who recommend placing the bulbs within a couple of inches of the plant tend to be those who don't use reflectors and have plenty of time to spend moving lights as the plant grows. Those who get good results with CFLs fixed a few feet above the plant tend to be running a lot of bulbs in small grow boxes lined with good reflective surfaces. I tend towards the view that it's the growers who make good use of reflectors on the bulbs and use highly reflective grow boxes, removing the need to place bulbs extremely close to the plant and adjust them daily, that are 'doing it right'. You can make passable DIY reflectors using beer cans.

As the plant is growing taller it will grow towards the brightest source of light. If you have one bulb that is much brighter than the others it should be placed directly above the plant so that the plant doesn't grow sideways. If the plant is surrounded by multiple equally-bright bulbs then the main stem will grow roughly upwards while individual branches and leaves stretch towards the nearest, brightest light source. Rotating the plant can help to ensure a nice uniform shape. As to whether it is better to place all bulbs overhead or surround the plant, again it comes down to reflection. In a well-designed box lined with mylar it's easier to place all the bulbs overhead as the light will reflect off the walls of the box and onto the sides of the plant. Without a reflective box and/or reflectors on the bulbs then you will need to get the bulbs very close and surround the plant or most of your light energy will be wasted. Even if surrounding the plant though, with bare bulbs and without a reflective box at least half of your light energy will be projected onto the walls of your grow room/closet. Unless those walls are very close and are at the very least painted white then that energy is wasted. Even white painted closet walls make a very poor reflector though when compared with a small enclosed box lined with mylar.

I hope this helps, and good luck with the grow

 

[bamfrivet]

Growing with CFL is great for a budget grow. However for the best results you have to make sure that you adjust the lights daily if not more than once per day. Put your hand on top of a leaf and get the bulb as close to your hand as you can with out it becoming uncomfortable. You also don't want to have like 1 high watt bulb sitting right above it and that's it. Growing with CFL requires having bulbs not only above but all around it. The more you can get around your plant the better. CFL lumens drop of dramatically after a couple of inches and doesn't penetrate through the leafs like a HPS or MH bulb. If you just keep the bulbs above the plant all the lower branches will stretch out like crazy trying to get to the light, then you'll have to steak up your branches.

As for trimming, you may need to if you are limited to only a couple of bulbs. Try LSTing your plant before trimming it up though. LST works great with CFL bulbs because you can keep the plant shorter and wider so you can get more coverage with the CFL. Like I said CFL lumens don't travel vary far so you don't want a real bushy center.

 

[towelie...]

growing with cfls is for people that cant afford a decent setup...

if you can afford it just get some real lamps

if you cant well get tons of little lamps and keep adjusting them daily

 

[virulient]

growing with cfls is for people that cant afford a decent setup...

if you can afford it just get some real lamps

if you cant well get tons of little lamps and keep adjusting them daily

I was going to reply. Then I saw this and I was like "wow now I don't have to reply". But I'm blazed, so I figure I'll just put in my 2 cents. Basically, just as he said, with CFL's you want to get more, small bulbs. Instead of getting a few, larger bulbs. You want a lot of little ones to surround your plant, keeping each one of them within an inch and properly spread out to get the best coverage. Enhance with UV-b to increase resin production. Adjust your lights at LEAST once a day. You can get extremely high quality buds when growing with CFLs. What lacks is the penetration, yield, and density. That being said, they will still grow some dank.

And, of course, if you can afford it pick up a nice HID light. If you got a small area look into a 400w magnetic HPS ballast with a cool tube and a Philips Mastercolor Ceramic Metal Halide. This is an extremely nice setup for moderately sized grow, and they offer a nice enhanced spectrum.

 

[frmrboi]

I was wondering if trimming would be a good thing for me to do. The bushier plant has lots of tiny, less developed branches that just look scrawny. should I trim some leaves to allow more light penetration? And how do I tell which ones to trim?

leave the leaves, trim the scrawny branches.

 

[robbye]

Thanks for the replies guys! Very helpful information, exactly what I was looking for.

Bosco- As of right now I'm one of those guys that just uses bare bulbs. However I plan on making some reflectors for them now so I can space them a tiny bit more. And my box is only painted white (couldn't find mylar at the local hardware store or walmart!) so I need all the light I can get.

Towelie- Yeah I'm pretty broke right now so I just stuck to CFL's to keep it simple and cheap. Now that I've been growing a little bit I wanna get rid of them and invest in a nice CMH bulb or two because I want to grow a few more plants and get a good two week harvest cycle going.

And as far as trimming, I think I'm going to wait until after I have some reflectors set up. Then I'll trim the branches that don't develop after that.

Again, thanks for the help. This is going to be my second grow, but only my first successful one. My first one was killed via the old paranoid roommate. ha

 

[MrBosco]

Hey Robbye. With bare bulbs you'd do best to take the advice of banfrivet and virulient above. Without reflection the bulbs will need to be close to the plant and surround it. You'll read all over these forums that CFL lumens drop off heavily a few inches away from the bulb and so they have to be placed close to the plant. This is of course true, but is also misleading. So long as you can efficiently reflect indirect light back towards the plant the bulbs can be placed much further from the plant and still get good results. You need only look at a car headlight to see how a well-designed reflector can make a massive difference to apparent lamp brightness at a given distance. Have a look at the threads below for info on DIY reflectors made from aluminium cans. These designs require mylar, though I have a feeling that polishing the inside surface of a beer can to remove the anti-corrosion layer from the aluminium would yield pretty good results.

https://www.rollitup.org/do-yourself/477877-diy-cfl-reflectors-single-multi.html
https://www.rollitup.org/cfl-growing/463748-light-foliage-remake-sticky-retarded.html

 

[robbye]

Thanks for the links Rosco! I have a few made, now i just wait and observe the results!