Yossu

Ah, PAR spectrum. Didn't know what that was until just now, but it's quite different from how I interpreted full spectrum. Thanks for the clarification.

You say it's full spectrum, but it looks very red. Can you clarify?

OK, so I can see the option to remove the previous text (usually, not always but clicking a few times usually gets there eventually), however it's pretty annoying that it happens. I've also noticed that I regularly get a red message below the text box that says "New posts within a short time frame are limited. Please wait 4 seconds before submitting." It leaves the textbox open with my message in, implying that my post wasn't made, however if I refresh the page, my post was made. Again, this looks like a bug, and is likely to result in duplicate posts as people think their posts haven't been submitted.

Thanks for the explanation. As you can see, I know little about these, but am learning fast! I'm going to try one warm white and one cool white, and see if there is any difference. Always like an experiment! Thanks again for all the help. At some point, I think it would be useful to summarise the info here and post it as a sticky. I'm clearly not the only one who is confused, and it would a great help to people like me to have it clearly summarised. Would you be interested in doing this? I would, but I don't know enough to be sure I'd be writing the right thing!

True enough, but as I have some plants that won't grow outside in the winter, and some that I want to grow inside this winter (sarracenia seedlings that I want to try skipping dormancy in the first year to see if they grow any better), I don't have much choice. I want to give them the best chance. As we are trying to simulate natural light, I would have thought that cool white bulbs were best, which is why I asked about this above. I was under the impression that they were the closest thing to natural daylight. I was surprised at the suggestions of using blue/red or warm white.

Just done some calculations, and assuming my schoolboy trig is correct, a 120degs angle at a height of 12" would give a spread of about 40" which is excellent.

Ooh, now you're confusing me again!

I was looking at the ebay ones linked earlier. I don't have any others to compare! So, based on the fact that they look like yours, I would presumably get something like the spread you do. Any idea what that would be at a height of around 12"? Thanks

Duh, obvious really! What sort of spread do you get? Thanks again

Looks excellent. Two questions... 1) What do you use on the back of the bulbs? Ty current setup uses standard fittings like you'd use in a room. These are fine, but add quite a bit to the height of the light. The spot where I'm looking to build my new growing area doesn't have as much height as I'd like, and I'm looking to find fittings that don't take up much space. Your look good for that. 2) What sort of spread do you get with those bulbs? I see they have 60 degs and 120 degs, and so I would probably go for the wider ones, but I'm a bit worried that with only about 12" from the bulb to the top of the pots, I would need a lot of bulbs (ie major cash) to avoid small pools of light with darker areas between. Thanks again

OK, that makes sense. I haven't yet worked out how I'm going to do the setup, so not sure how I would manage a combination. I think I'm going to end up with a wide area, but not too deep (front to back), so I would have to alternate the lights along the length. Thanks again

That's something I was going to ask about. If I grow them under these lights, and then want to move them out (which I would when they grow bigger), how well would they adjust?

Any reason why you chose warm white? I thought that cool white wold give a wider spectrum. Isn't that what daylight bulbs are?

Would you believe it! Didn't have the problem this time! I'll keep the tip in mind, thanks again.

Thanks for the tip. Can't say that was a very obvious answer! Can't try it until I try a second post in the topic, but will let you know what happens.

OK, so I'm going to have a go with white and see how I get on. You said you could find them for around £10 on ebay. I just had a look, and the only ones I could see were low wattage, like 3W and 5W. I didn't see anything like the 35W mentioned here. can you give me an idea what you mean? Any links would be great. Thanks again

Ulp, what a lot of information! What options would you choose to get something comparable to the bulb we were just discussing above? I'm interested to know how the price compares. Not sure if they are similar though, as the description says they need a power source and have to be mounted on a heatsink. Sounds like it's not for me!

I find that when I click the button to post a reply, often I get my text left in the box, and it's very hard to remove, especially if I quoted someone. Even refreshing the page doesn't help. Anyone else found this?

It sounds to me like those white ones are going to be a good option. Unless anyone can point me to a cheaper (but not necessarily cheap) alternative, I guess I'll have a go and see. As they are a decent size (about 5" diameter), I guess they should light up a decent area, so it might be worth trying one over some plants, and a 6400K CFL over another, and see if there is any difference. Thanks again to all for the help. I can't say I'm clear on any of this, but it seems like this might be the right direction to try as a starter.

That sounds good (not withstanding your last comment), as they are white (so looking better) but intense. Maybe I should try some of those. What do you think of mander's comment about cheaper ones on eBay? How would I know what is comparable?

Hmm, so it's a toss-up between the plants looking nice and growing better? I suppose that comes down to where the lights are used. For a growing area, where I want to get some small plants into a big enough state to sell them on, then colour isn't so important to me, but in my display area, I guess white would look better. Do you have any idea what wattage white you would need to get the same as the red/blue? I mean that suppose you had a 20W red/blue one, what wattage of white would you need to have 20W of red/blue light, as well as the green. Don't know if it's posisble to say, but it would be useful to be able to compare. Do you know what sort of white LEDs I would use if I were to use them? I had a look, but got so confused at the enormous choice. If you could link to an example or two, it would help me make a comparison. Thanks for all the help.

Meaning not so good for growing on? I'm looking for lights for post-germination plants.

I thought the blue/red ones were supposed to be better? Don't get me wrong, I don't speak form any position of knowledge, just saying what I've read. If you were to ask me, I would have expected white to be better as it simulates what they would get in the wild, BUT that all assumes it gives a full spectrum. Do white LEDs give out that? Trouble is, none of the reviewers came back after a month or two and updated their reviews, so you have no idea if it actually works or not. If, as manders said, you can get white LEDs for £10, then they would probably be cheaper overall. Oh I'm confused! Can someone tell me what to do!

Do you have any links for those? £20 for 36W is within my budget, so I would be interested. Me too, that's why I started the topic. I'd like some of the experts to give some clear advice. Be a huge help.

Same, meaning these specific one,s or the same in general? The reason I ask is because I brought the subject up in another thread, and Dieball (who started the thread, and has some great lighting there) commented that these were "most probably just a piece of garbage. Even a few Phillips Tornado bulbs would give better light." I'm really an ignoramus with this stuff, and am trying to work out what to do. On the one hand, I want more lighting, and LED seems to be the way to go, but commercial stuff is very expensive. Then you have ones like this, that look the same to the common man, but are very cheap. What's a boy to do? Any advice welcome, as I'm confused!