How well do flowering plants deal with lighting changes..

I was just wondering if anybody knew how it would +/- effect a plant if there was a sudden increase in lighting during the flowering stage. Here is the deal, say I was running (2) 23watt 2700k CFL's that have a lumens output rating of about 1,600 lumens.

So only averaging about 3,200 lumens of pure 2700k which are being run along side a 23watt 6500k 4-pin CFL. Obviously for flowering I would want more than 3,200 lumens so if I were to add another 23watt/1600 lumen and a 40watt/2,750 lumen bulb bringing my average up to about 7,550 lumens (+ 1,600 lumens of 6500k = about 9,150 lumens total.)

My question is, would they easily adjust to the sudden environmental changes?

anybody?

your plants will not suffer if you add more light. they will love it quite a bit. you could and should add even more light if it's doable for your situation.

Correct me if I'm wrong but you're saying you currently have 2 23W 2700k and 1 23W 6500k? How much square footage do you have? Your Lumens to square footage will help determine the yield. You should read chapter 9 of this book:

http://books.google.com/books?id=fERzFsZhdxYC&lpg=PP1&dq=growing marijuana&pg=PA169#v=onepage&q&f=false

it has great information about light. From what I've gathered its best to have as much 6500k light during veg and then as much 2700k for flowering as possible. The book can help you calculate an ideal amount for your growing situation and needs.

Increasing amount of light should only help them grow, of course you'll have to adjust other things as well. Temperature for instance, can increase when adding more lights.

LucidLuke said:

Correct me if I'm wrong but you're saying you currently have 2 23W 2700k and 1 23W 6500k? How much square footage do you have?

Click to expand...

2' wide x 6' high x 2' deep.. it's a really small space with 1 plant and I know I need to add more light I have already said that. That book is all about HID's and I said I was using CFL. How does that help me at all? I know my aim is as close to 10k lumens as I can get, the only thing is I've just been building it up gradually.

flowering is controlled by a non-mobile hormone that breaks down in light. Genetics plays a part in this, but most plants will start flowering when they consistently receive 12 hours of dark. This allows enough hormone production to switch cycles. Even small amounts of light can kill the hormone and interrupt the dark cycle, but as long as you maintain that 12 hours of dark and they receive enough light to live they will continue to flower. If they get less than 12 hours then you run the risk of reverting back to a veg, and that's real time consuming and I would imagine stressful on the plant.

i would also reccomend positioning some of that light on the side or getting a few tubes for the side. and try not to get too hung up on lumens. all the lumens in the world won't help you if the light is not actually hitting the plants, but when using cfl more is always better if you have the space. as for the spectrum, yes the redder light is ideal for flowering but remember that the sun does not put out just one spectrum of light, even during late summer evenings. the ability to mix spectrums is a kind of bonus for using cfl. don't be afraid to mix it up.

Okay, so far right now I have (3) 23w 2700k and (1) 40w 2700k and (1) 23w 6500k,
total lumens: about 9,150 in a small space and I pretty much vegged the whole thing with the (1) 6500k, I didnt add the first 2700k lights until about 1-2 weeks before I started flowering.

The book does mention CFLs but just a brief mention, CH9 is a long one, keep reading. CFL, HID, HPS or MH, doesnt matter when discussing the light spectrum the plant uses. Some people mix the light, (similar to what you have) and use a heavier blue to red ratio during veg and then switch to heavier red to blue ratio during flower. Personally I like to use all 6500k cfls for veg and all 2700k for flower, why you ask? Yes the sun doesnt just emit blue or red light, but there are reasons blue is sometimes stronger than red and vice versa such as a phenomena called "Red Shift" and the fact that the earth is on a tilted axis that rotates and orbits the sun. With that said reception of blue light is stronger when the sun angle is as close to directly overhead (usually spring to summer season) the days are also longer which is why 18/6 or 24/0 hrs of light/dark are suggested for flowering. Then when the sun angle is lower (fall to winter season) red is received more than blue and for shorter periods of time (which is why 12/12 is good for flowering). The idea to indoor growing is that you want to create the most ideal conditions for growing and producing THC, one way to do this is to mimic exactly what nature would do, but why do that indoors, just move outside if that's the case. So since you are "playing god" so to say, you can (ideally) adjust every environmental aspect of your growing area to be the best for your plant, and in doing so you can "cut the crap" and give the plant only what it needs when it needs it.

I hope my ranting isnt too confusing and is of some help to you.
All that being said, your plant looks strong and healthy. I would put the lights as close to 2''-4'' from the leafs of the plant and like Total Head mentioned I would put some on the side when you start flowering. If you have proper ventilation, the lights shouldn't get too hot, cuz they're cfl, but having a small fan to keep them cool will also keep the plant from getting over heated. My best advice would be to goto a bookstore and try reading as much as you can in any Cannabis Horticulture/Cultivation book or find a Marijuana Grow Bible or that one on google. Another quick opinion of mine that might be helpful for you is that you have to try harder to kill one of these plants than to grow it, course there's a lot of work in making the perfect bud but even cutting corners and just doing minimal work taking care of it will get you a halfway decent production.

I'm just a noob starting my first grow (link in signature) and so far this is all I know from going into bookstores and reading stuff online. I'm almost ready to flower, not far behind you Wicked Pagan.
\m/

CFLs Page 208-214

http://books.google.com/books?id=fERzFsZhdxYC&lpg=PP1&dq=growing marijuana&pg=PA208#v=onepage&q&f=false

don't neglect T5's either, they put out more light, and only cost a little more. They are going to give results kinda midway between cfl's and HID's (part of this is that like cfl's they can be much closer to plants). Look for fixtures with individual reflectors that maintain dense bulb placement (this is really the case on any tube fixtures).

I'm actually 12 days into flower, keeping it small. The preflowers are coming in kinda slow, I think anyways.... this is my first grow but I still have an idea of how things are supposed to be. That is why I started adding more lights because I noticed that the preflowers should be developing faster. Check this out: https://www.rollitup.org/indoor-growing/347992-alright-i-think-i-finally.html#post4386674 hopefully its a girl.

get the lights closer to the plants. ideally within a couple inches. i mean it about the side lighting. it will make a major difference. i used to use t5/cfl and the difference in growth is very apparent.

I'll see what I can do. Certainly a good idea, thanks.