LED light set up help.

[Alvaro78]

Hello beautiful people,

I come here to ask for some help regarding grow lights. I am a totally new when it comes to LED lights and such so I was looking for some help.

I want to set my LED lights in a ikea shelf which will be aproximately 3 meters away from a west facing window. The shelf won't be directly facing the window but facing it to one side. I plan on putting there my phals and some of my cattleyas. I did some quick research and here in Europe I came across some decent looking lights from SANlight called SANlight FLEX II. They have them in different options: 10W, 15W and 20W. And here's my problem... I don't know which one to choose haha... or how many for each shelf. The shelf will be aprox. 1.5 meters long.

I also have a question regarding my orchids that will remain near my west facing window. I am worried that my cattleyas won't bloom due to the lower sun hours during winter. I live in Spain so we thankfully have longer sun hours during the winter of about 9 hours compared to other european countries. So my question is also regarding them having enough light to bloom without any supporting grow lights. I have limited space so I would also like an answer to that. If the answer is that they are not that likely to bloom I could maybe look for some lamps to give them more light. If you have any suggestions available in Europe it would be awesome too.

Thanks a lot for reading all this, I hope you could properly understand what I am asking for since English isn't my first language.

[estación seca]

rbarata answered this in another thread.The techical information for these lamps is on the manufacturer's Web site:
SANlight FLEX II-Series - sanlight.at

The important information is the PPF, shown for each lamp. I don't use lights but people here who use them can help.

[Alvaro78]

Thanks a lot Estación Seca. Apparently the 10w one has 25 PPF. I am more familiar with PPFD but I don't really know how to convert it. I guess I would just need to convert it and see if the PPFD is in the correct parameters for cattleya growth?

[estación seca]

I didn't look in detail at the information. PPF is the absolute number of photons emitted. PPFD is the density of those photons striking a specified area. This depends on the distance from the lamp. Calculation and knowledge of the light pattern at the chosen distance is needed. I would write the manufacturer and ask, or look for online discussions of this lamp.

[Alvaro78]

I'll try contacting the manufacturer. I hoped I could get some guidelines from some people that use grow lights about how much PPF would be enough for my needs. It's honestly a confusing topic when you have 0 idea about lights haha. Thanks

[Alvaro78]

Hello guys I come here with some information I gather and I hope you can help me. I finally understand more or less how LEDs work and how they're measured.

I now have the SF300 by Spider Farmer as my prime option but I have some questions related to my own set up. I attached a picture with the PPFD grid of these LEDs. The measurement was done in 2'x2' (60cmx60cm) and as you can see in the center it gives good PPFD values but when you get further from the center it diminishes quite a bit. My question is knowing if I place some of my cattleyas at the edges would they be getting enough light and some from the center too? Or would it just be too little for the cattleya for it to bloom.

I also now understand how DLI works too as a measurement and adjusting the hours I would put on the light if I average 200 PPFD I could leave my LEDs on for 14 hours. The problem I see is that maybe as I said the cattleyas further from the center wouldn't be receiving those 200 PPFD minimun. I hope you can provide me with some help and telling me if these ones are good enough.

Thanks a lot!

[camille1585]

I'm a bit late to this thread, but here's my thoughts...

A few questions first:
* Your say the shelf is 1.5m long, but how wide is it?
* What will be the distance between the top of the plants and the lights?
* Are the plants staying on those shelves year round or do they get natural light in the summer months?

The answers to the first 2 questions are really important in the total equation.

As to the placing the Catts on the edges of the light coverage, where the PPFD is lower, why not have Catts in the middle and Phals on the edges? Otherwise, looking at the PPFD map, the solution (but also depends on the distance above the plants) would be to have 2 lights in parallel per shelf if it is more than 30cm wide.

I have the previous version (Flex I) of the Sanlights which I use as supplemental light in the winter (I'm in the Netherlands, so the lack of light in the winter is far, far worse than in Spain..). I got the 20W versions, which at 90cm are the length of my shelves, and 1 per shelf since the shelf is narrow (27cm) and because the shelves are directly behind a south facing window. If they had been wider shelves I would have added a second one to reduce the edge effect.

I did take one sanlight to work with me once (I worked in indoor farming up to this year) to measure the PPFD at different heights, and it was quite high at 10cm distance! I'm trying to find the notebook where I wrote this down, but I think it was around 200umol/m2/s

The lights hang only 10-15cm over the top of the plants. This was too much light for the Phals so I reduced the duration from 12h to 8h. I have a couple Catts, these sit in the middle of the shelves. I get blooms every year, but it's important to note that they also get a lot of natural light as well the rest of the year!

[Alvaro78]

Originally Posted by camille1585

I'm a bit late to this thread, but here's my thoughts...

A few questions first:
* Your say the shelf is 1.5m long, but how wide is it?
* What will be the distance between the top of the plants and the lights?
* Are the plants staying on those shelves year round or do they get natural light in the summer months?

The answers to the first 2 questions are really important in the total equation.

As to the placing the Catts on the edges of the light coverage, where the PPFD is lower, why not have Catts in the middle and Phals on the edges? Otherwise, looking at the PPFD map, the solution (but also depends on the distance above the plants) would be to have 2 lights in parallel per shelf if it is more than 30cm wide.

I have the previous version (Flex I) of the Sanlights which I use as supplemental light in the winter (I'm in the Netherlands, so the lack of light in the winter is far, far worse than in Spain..). I got the 20W versions, which at 90cm are the length of my shelves, and 1 per shelf since the shelf is narrow (27cm) and because the shelves are directly behind a south facing window. If they had been wider shelves I would have added a second one to reduce the edge effect.

I did take one sanlight to work with me once (I worked in indoor farming up to this year) to measure the PPFD at different heights, and it was quite high at 10cm distance! I'm trying to find the notebook where I wrote this down, but I think it was around 200umol/m2/s

The lights hang only 10-15cm over the top of the plants. This was too much light for the Phals so I reduced the duration from 12h to 8h. I have a couple Catts, these sit in the middle of the shelves. I get blooms every year, but it's important to note that they also get a lot of natural light as well the rest of the year!

Thanks a lot for taking the time to answer me camille! I'll try to answer all the questions.

About the shelf being 1.5m long. I forgot to mention I decided to change that too since I wouldn't have enough space in the end for where I want to put it. It finally would be 90cm wide.
Regarding the dustance between the top of the plants and the lights it would depends since I can easily adjust the height of each shelf but I want to be able to place them quite close if possible to optimize the most space.
My plan with my orchids there is having them on the shelves year round. The thing is due to the distance they are in I don't think they will be receiving that much light during fall and winter, just very mild. In the summer they will get some direct sun when the sun is setting but just for like an hour and a half and not all of them since they wouldn't be facing the window.

I thought of placing 2 of those LEDs parallel to each other but that would be a bit out of my budget for the amount of orchids I have sadly.

About the Sanlight LEDs you have mhmm They are 90cm so they would fit perfectly but the issue I have is that since I wouldn't give them much natural light I don't know if they would be enough as a sole source of light. The manufacturer didn't provide me much of a PPFD estimate or something related for me to calculate. They just give a PPF of 48 µmol/s but I don't know how to interpret that into PPFD. Do you think placing 2 of those 20W on each shelf would be enough and actually spread more of the PPFD for all the orchids?

Thanks a lot once again!

[camille1585]

Wow, 1.5m by 90cm is a really, really big shelf. Unless the 90cm is a typo, you're going to need more than one row of lights I think.

If you only had Phals I think the Sanlights could be enough, but like you I'm not too certain about the Catts. Have you seen this thread yet on another forum? I think it gives you a good idea of the set up needed, and he's using Spider Farmer SF600 LEDs, so more powerful than the ones you were looking at.
Cattleya jenmanii and light intensity | Slippertalk Orchid Forum

For Phals 'optimal' DLI is around the 4-6mol/m²/day, so with a 12h day that works out to 95-140umol/m²/s PPFD. For Catts I found a range of 10-15mol DLI, so 230-350 PPFD for 12h. I'm not a Catt expert but more than 12h light might not be a good idea as I recall reading that some Catts are sensitive to daylength, but I can't remember the details.

PS: I had written this reply last night, but my session timed out and the forum 'ate' my reply. So I had to start all over again this morning!

[Alvaro78]

Sorry! It indeed was a typo. I wanted to say the shelf would be 90cm long instead of 1.5m.

That thread was actually so helpful so thanks a lot! I imagine I could try to adjust the DLI to make up for the weaker lights of my SF300 model since it shows they can still bloom from a lower PPFD if adjusted.

The cattleyas more sensitive to daylength would be something like a walkeriana but it is something still up for debate from what I read.

Thanks a lot once again for taking the time to help me!