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Distance from Lights?

Vbkid

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So for years now, most of my plants have been under 4-Bulb T5 fixtures, maybe 9 inches form them.
I've recently added some mars hydro LED fixtures to a separate shelf. I'm afraid of frying any plants (mainly sundews and pings), and am wondering if 9 inches is going to be too close? Wondering if anyone could offer advice for the best distance to an LED fixture for various types of plants?

Thank you,

Kyle
 
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When I replaced most of my T8's with LED, the change in distance didn't fry anything, just dramatically increased red color for a few months before they all settled in (still far more colored than before though). LED's are not supposed to be high heat lights, so temperature-wise they shouldn't be any worse, and brightness-wise the plants just need time to acclimate.
 

pappydew

I hate bugs. Carnivorous plants get me.
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Which model do you have? Those Mars fixtures are pretty powerful LEDs, they won't need to be that close. But as Hawken said, heat's less of an issue compared to fluorescents.

The only thing I would be especially careful about is that Neps might show signs of "light burn" if they're getting too much light. Most dews, Pings, etc. probably won't mind getting blasted with more.
 

adnedarn

I'm growing CPs in the Desert of Tucson, Az
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If you're happy with the way your plants look under your current lights and want to match that, it is likely that your phone has a light sensor you can use. Download an app and you should be able to see the data then you can measure your old lights and adjust the new ones to provide a similar intensity. For my Samsung I use an app called "Galaxy sensors".
 
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Assuming you have the Mars hydro 300w, 9 inches is unnecessarily close, especially for sundews and pings. I would keep the light at a height of 18-24 inches above the canopy of your plants. But keep in mind that the light intensity varies according to where you place a plant under the light. This is a PPFD map at 18" for the mars hydro 300 (taken from the mars hydro page on amazon): https://images-na.ssl-images-amazon.com/images/I/61L2MVc0p1L._SL1500_.jpg

Place plants that need most light under the middle of the light. If you're unsure of how much light a plant can take, place it a foot away from the middle and start moving it towards the middle little by little. Once you notice it coloring up nicely, you're giving them enough light. Lots of my pings like to be BLASTED with light.

If you're happy with the way your plants look under your current lights and want to match that, it is likely that your phone has a light sensor you can use. Download an app and you should be able to see the data then you can measure your old lights and adjust the new ones to provide a similar intensity. For my Samsung I use an app called "Galaxy sensors".
That approach usually doesn't work well for blurple lights. Though depending on what phone you have, this approach may be a good starting poing: https://www.youtube.com/watch?v=AjkEJjlzGv8
 

Vbkid

Getting There...
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Madison, WI USA
Thanks for all the really useful info. I've downloaded an app to test the output and will be scaling the plants back a bit!
 
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