What's new
TerraForums Venus Flytrap, Nepenthes, Drosera and more talk

Register a free account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members through your own private inbox!

Lighting Help

kath

Katherine
I have a new grow rack, and I'm trying to work out how to light it.
I currently have access to:

a 20W compact fluorescent
an 8W fluorescent tube

Which obviously isn't going to be enough! But what is 'enough'?

I'm planning to grow lowland nepenthes on the top and highlands on the bottom. I've heard highlands need more light than lowland nepenthes, but how much light is this? Is it possible for me to have lots of small lights to add up to the wattage, instead of 1 big tube light?
I'm looking for measurements in Watts.
 
if your growing the lowlands in a terrarium you might be able to use 2 compact flourescents. also you can move the rack infront of a sufficient window and put the highlands on another rack. just a thought. somone with more experiance will chime in later im sure.
 
Kath,

What is enough is a wide open question. What is the area you are trying to illuminate, What is the distance to the bulbs, What is the light requirements of the plants, What is the PAR value of the bulb you are going to use, What is the PUR value of the bulb/reflector combination you are going to use, Is the plant in flower, Is it actively growing, what is the photoperiod etc etc etc

When it comes to lighting, substrates or fertilizers then black and white answers are rarely available... there are just too many unknown and interdependent variables that must be considered

But, as a baseline... 20w per square foot would be a good starting point IMHO ( 10w per sq. foot would be an absolute min IMHO)

Light is the single most important variable in plant growth IMHO, if you don't have enough light then nothing else you do can make up for it

There is an old hillbilly saying, its hard to turn doo doo into ice cream, and even if you could.... who would eat it ;)

In other words, don't skimp on lighting... get what you can with what resources you have available to ya...

Have a look at this ref, it is basic but a very good start

http://geocities.com/butchtincher/research1/grolux.pdf

HTH's
Av
 
I don't know much about footcandles and such but petshops sell lights that are designed for plant growth and wavelengths.
 
2: 40 watts on each shelf would be great!
 
Ok. So aim for 40W on each shelf. I just wasn't sure, because I've heard of lowlands wanting less light, and highlands wanting more.
 
You can always move plants closer or further away from the lights. Raise a pot up to get it closer.
 
HPLH is suggesting a 2 tube fluorescent fixture??. Which I think for you would be the energy saver ones that put out 36 watts each tube for a total of 72. The old ones used to put out 40watt for each tube.

Have you read through the two sticky threads on lighting and calculating light?
 
I'm getting really miserably confused with everything to do with the grow rack, and I'm beginning to regret buying it.

1. I can't find any lighting that is the right size for under 50 bucks.
2. Any lighting I do find has no plug, it is ceiling/wall fixture
3. I have no idea how to heat it succesfully.
4. My fan can only run off 12 volt battery, and I'm not even sure how to wire it to this

I really need help - I feel like I've been thrown in the deep end. What was supposed to be a simple gift is quickly turning into an expensive nightmare.
 
  • #10
Take a deep breath ;>

1. If money is tight forget about the heating issue for now. Lighting is more important and you shouldn't skimp on it. If the lighting is poor the plants will never grow properly.. bottom line.

2. The simplest fixtures are those 2 tube ceiling fluorescent fixtures yes. And yes they need to be wired. Which isn't too hard.

3. You don't need to light every shelf initially if you don't have enough plants to fill it anyway. So only buy what you need and when you need.

4. If money is tight just wait until you have more funds.. Hard to do I know! But you will be much happier in the long run with the results.

5. To run a 12v fan you would need a simple transformer to take the AC power and convert it down to 12v DC(I am suspecting) Again... easy to wire.

6. If you are so concerned about heating and changing the environment I would suggest rethinking what you want to grow for now. Changing environmental conditions to grow more specialized plants is difficult and adds alot of cost in equipment and utility fees. Better to start with plants that will be happy in the current conditions you have.
 
  • #11
Ok. Thanks for the help. I have solved the fan problem. I wired it to 2 6 volt batteries and gave it a switch and built it a plastic casing. It's all in fine working order.

I've decided to only set up the top shelf so far, so I'm looking for ways to heat. I have 28W of light already for the top shelf, so I just need to look for a little fluorescent light. Even 18W will bring it up past 40W. Which should be enough to start with germinating lowland seeds, shouldn't it? I will add more lately, but just temporary because once the seeds are ready I have to accept them, Nep seeds don't have a long shelf life!

I've found a way (I think) of succesfully heating it until I can find an affordable electronic heat pad. I was thinking about one of these things:http://www.mavco.co.nz/index.aspx?site=465&page=3979. The only thing is they don't last for more than an hour before they begin to cool down. However, maybe I could get around this somehow?
 
  • #12
Kath,

you need to slow down a bit, first you need a "wall pack" power supply for your fan. Something similar to some printers or other small devices use. That way you can use the normal run of the mill light timer to control it. I have mine on the same timer as my light and humidifier. That way when the lights are on the fan is on...

With batteries your voltage will slowly drop, in other words your fan speed will slowly decrease as the batteries dies. Plus you will have to be there to turn it off and on.

Your idea for heat would be less then ideal as well... much for the same reasons. You will have to regenerate these hourly... and then the heat will peak and then drop...

neither method is anywhere close to constant and both require too much attention... at some point you wont be at home or someone will forget to do it for you

slow down... get the lights, you may find that if they are in the enclosure.. they might produce the heat you need... if not then work on that and the fan next.

Rushing into this will only ensure failure... Tony has given you some wise advice

HTH's
Av
 
  • #13
The grow rack is at my nanas, and she is home all day and everyday. She is very good at remembering my plants, because most of my collection is at her place, and none have died yet, in the year they've been there. So I think the fans all sorted, thanks :)

Also, the fan is purely there for air circulation. I plan to have it on for 2 hours a day, tops, just to move the air around so it doesn't go stagnant. I'm currently looking at my heat pad options, but have found a few pet heating pads for under 50 bucks, which supply constant steady heat for 10-20W. The only problem is that most of these don't say what temerature they heat to. I've found one that supplies constant steady hat of 25 degrees celcius, but would this be enough?

And I can definitely tell you that fluorescent lights won't heat it up nearly enough if a 150W incandescent bulb running for 4 hours can't!
 
  • #14
You should be able to find thermostat controls for seed germination tray heating mats. They have a soil temperature probe and shut the current off to the mat when the set point is reached.
 
Back
Top