LED system to grow indoor

[Jade]

All my orchids are growing on windowsills, but now, due to the large amount of plants, I decided to grow them in a kind of greenhouse( the ones that we can find to home depot, just to say).
I was just wondering what kind of LED can I use. I've found one with this written on it: T4, 30W, 2100 lumen.
Is this good? I mean, is it enought to grow my orchids? How many orchids can I grow under this light?

[Dendy83]

I have a pretty basic set up, but I have already noticed a huge difference in growth from my orchids since using these lights. I have a simple black wrought iron stand and use a clamp lamp to clamp to the iron.

Here are the lights.

Then I've attached a timer to them so they automatically turn off to whenever I set them.

Like I said, these are pretty basic, if budget and space allows I say go for lighting through First Rays Orchids.

[naoki]

Jade, you can grow orchids with any white (or red+blue based) LEDs (as long as you have enough of them). There are big differences in the performance/efficiency among LEDs. At the bottom, efficiency is lower than fluorescent light, and at the top end, the efficiency is similar to HPS. Generally, there is a correlation between the efficiency and price (unless you go with DIY LED, which is pretty easy to do). But there are some expensive models which don't perform well. So shopping for LEDs is a bit more complicated than for other light at this moment. So it is either you pay now, or you'll end up paying a lot later (for the electricity).

The one you referred seems to have a low efficiency. Lumen isn't a good index for plant growing, but 70lumen/W is rather low. Even house-hold LED bulbs such as Cree and Philips have higher efficiencies (e.g. Cree 9.5W soft white = 84.2 lumen/W). With that, 30W will probably cover about 2 sqft (40x40cm) for moderate light orchids (a bit more than Phals, but less than Catt).

I understand photosynthetic efficiency is not the only criteria to chose LED. For example, less heat emission is important in a small enclosed space. But less efficient LEDs are basically less efficient because electricity is getting converted to heat than to light.

[Jade]

thank you for your advices!

[Plodde]

Originally Posted by naoki

Jade, you can grow orchids with any white (or red+blue based) LEDs (as long as you have enough of them). There are big differences in the performance/efficiency among LEDs. At the bottom, efficiency is lower than fluorescent light, and at the top end, the efficiency is similar to HPS. Generally, there is a correlation between the efficiency and price (unless you go with DIY LED, which is pretty easy to do). But there are some expensive models which don't perform well. So shopping for LEDs is a bit more complicated than for other light at this moment. So it is either you pay now, or you'll end up paying a lot later (for the electricity).

The one you referred seems to have a low efficiency. Lumen isn't a good index for plant growing, but 70lumen/W is rather low. Even house-hold LED bulbs such as Cree and Philips have higher efficiencies (e.g. Cree 9.5W soft white = 84.2 lumen/W). With that, 30W will probably cover about 2 sqft (40x40cm) for moderate light orchids (a bit more than Phals, but less than Catt).

I understand photosynthetic efficiency is not the only criteria to chose LED. For example, less heat emission is important in a small enclosed space. But less efficient LEDs are basically less efficient because electricity is getting converted to heat than to light.

Thank god I found you! I just changed to LED Lights, AgroLED 12 watt lamp, for my small terrarium. Now, I know nothing about lights but it seems like 12 watts is very weak. There's 7 red, 3 blue, 2 white, 1 watt LEDS. Is this strong enough for orchids?

[Erin410s]

This is very helpful information. I have been running out of room on my windowsill as well and was thinking about starting an indoor grow chamber but I didn't know which light source to use.

[naoki]

Plodde, I'm pretty sure you CAN grow orchids with your LED grow light (I'm not familiar with that particular model). It is a matter of placing it at the right distance. Note that human eyes are most sensitive to green light. So when you see red-blue based growlight, we feel like that it is weak (plants may be getting more than enough). It is not easy to set the distance between R+B light and plants (unless you can buy an expensive light meter for plants called Quantum PAR meter). So you have to do trial-and-error.

I think this is the one you are talking about:

https://www.sunlightsupply.com/shop/...-full-spectrum

Unfortunately, it doesn't provide any relevant specification. But it is very expensive (so I hope it is a good one). With the similar price, Philips GreenPower, which Ray carries, has very good specification. If you are handy, you can get 50W of LEDs (with very high efficiency; Vero 29, Cree CXA3070 etc) for the same price. But you already have it, so you probably won't be in the market to get another one!

Erin, I personally think that DIY LED is the cheapest and best way at this moment. Even though it is pretty easy, it is not for everyone. Some commercial LED fixtures are really good, but the good ones are still expensive initially. So it may be safer to go with fluorescent light (either T8, T5 or T5HO) because variation in efficiency among LED fixtures is pretty high (and you need to know which one is the good one if you care about efficiency).