Growing Succulents and Cacti Under LEDs

[Jonny Klobber]

I have been using a couple of Spider-Farmer SF1000 lights over my succulents and cacti for about a year now. Plants are all alive and healthy but I'm not getting the sort of growth that I got when I had them at our previous house (they got a ton of natural sunlight there). I'd like to pick up some sort of light meter to see exactly what readings I'm getting so I can modify as needed...

My questions are:

1. Could anyone recommend an affordable light meter for this? A quantum PAR meter... Or whatever I'd need to accurately read all the relevant parameters.

2. What are the key parameters to check - PAR, PPFD, Lux, Foot Candles?

3. Where SHOULD those numbers be for succulents and cacti? In my collection are a few Crassula (jade) sp., Pachypodium, Euphorbia and on the higher end for light requirements, a totem pole cactus (Pachycereus schotti).

Thanks in advance!

 

[oneeye]

Just drop your lights lower for the maximum output of the LEDS. Go slowly to make sure the plants can take the lumens. You will never be able to match the Sun, however, mixing LED with HPS (high-pressure sodium) will come very close. Post a photo so we can see our garden.

 

[Jonny Klobber]

Thank you. I can certainly do that. I would like to get some suggestions for a light meter and some numbers/parameters to shoot for. Anyone?

 

[Jonny Klobber]

I’ll post a pic of the setup tomorrow.

 

[oneeye]

You need to use a par meter for LEDs. Don't get a LUX meter because it doesn't work with LEDs. You can download a app on your smartphone and use your phone. Here is a par meter on amazon. https://www.amazon.com/Quantum-PAR-Meter-Precision-Rechargeable/dp/B08JRPQ4L6

 

[oneeye]

The best PPFD/PAR range for your plants!

• Between 200-400 PPFD: This is great for seedlings, clones, and mother plants.
• Between 400-600 PPFD: This is great for early to late stage vegging cycles.
• Between 600-900 PPFD: This is great for the flowering, fruiting, or budding stage of plants.

Since you are going cacti I would think you should also be concerned with the Seasonal photoperiod. How many hours a day you run the lights. You are on a timer correct?

 

[Jonny Klobber]

Very helpful, thanks oneeye. I'll pick up a PAR meter. Here are a few pics. You can see that I have a DIY three-sided wooden screen hanging from the ceiling to cover the lights (otherwise anyone walking into the room would get blasted with light from the SF1000's. Also, keep in mind that I just repotted, removed three 30-36" trunks from, and pruned back the Pachypodium HARD. The pot was completely filled with huge tap roots and masses of fine roots (the whole thing probably weighed 85-90 lbs), so I basically removed about 80% of the plant(s). The center jade in the back has also been pruned and the small fluted/gollum jade in the front is actually just 5 recently pruned branches from a mother plant that I gave to a friend. I should have taken pics last week! But you get the idea.

 

[oneeye]

Very helpful, thanks oneeye. I'll pick up a PAR meter. Here are a few pics. You can see that I have a DIY three-sided wooden screen hanging from the ceiling to cover the lights (otherwise anyone walking into the room would get blasted with light from the SF1000's. Also, keep in mind that I just repotted, removed three 30-36" trunks from, and pruned back the Pachypodium HARD. The pot was completely filled with huge tap roots and masses of fine roots (the whole thing probably weighed 85-90 lbs), so I basically removed about 80% of the plant(s). The center jade in the back has also been pruned and the small fluted/gollum jade in the front is actually just 5 recently pruned branches from a mother plant that I gave to a friend. I should have taken pics last week! But you get the idea.

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I love your garden.

 

[Jonny Klobber]

 

[Jonny Klobber]

I love your garden.

I picked up a PAR meter yesterday... At the current height of my lights I'm only getting between 75 and 160 PAR readings at the tops of my plants. This is obviously a bit too low. According to the meter, I'd need to lower the lights to about 6" above the totem pole cactus to give it the light it needs (800+ PPFD). This isn't really practical for a few reasons, but mainly because if I lower the lights that much it won't be possible to lower my screen far enough to block the light from blinding people in the room unless I cover up the tops of some of the plants... Maybe there's a better fixture I can use that will put out more light and reach further down? I need to research this. Kind of a drag to have to buy new fixtures, but I think that would be preferable to lowering the lights that much... At least I know why the plants haven't been growing...

Any suggestions?

 

[Jonny Klobber]

Looks like THIS might be a good fixture for me:

Mars Hydro SP 6500 Samsung LM301B 650W Greenhouse LED Grow Light

www.mars-hydro.com

PAR readings are much higher at a given height compared to the fixtures I have. Anyone have experience with Mars Hydro?

 

[oneeye]

Looks like THIS might be a good fixture for me:

Mars Hydro SP 6500 Samsung LM301B 650W Greenhouse LED Grow Light

www.mars-hydro.com

PAR readings are much higher at a given height compared to the fixtures I have. Anyone have experience with Mars Hydro?

Thats a lot of light wattage.

 

[Jonny Klobber]

Thats a lot of light wattage.

I picked up that fixture and wow, it's got a lot of power! I have gradually raised it to about 75% strength, and at 30-36" above the plants, the tops are getting 600-850 ppdf, and the short plants are getting 180 up to 250. So I THINK I should see some really good growth now... We'll see...

 

[oneeye]

Wow, that's a lot of light, so be careful and acclimate your plants slowly. Its easy to burn plant tissue with LED because of the spotlight diodes are so concentrated. So watch your plants very closely until you are dialed in. Remember succulents hardly grow much even outdoors. I love your garden keep me posted.