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KNVB
08-23-2006, 03:17 AM
Hi...

I have a small grow going and i'm monitoring the relative humidity. I am sitting at around 45-46% RH with three seedlings under 24hr flouro (only a few days old). Everything I have read says i'm about 10-15% off of the optimum level. I am not running fans on the seedlings but do have a gentle fan that I can use to circulate air without disturbing/shaking the plants.

What can I do to bump up the RH? Is it important that I do so?

My idea has been that I could leave a small pot full of water in my grow room under the light, monitor its affect on the RH as it evaporates and adjust accordingly... Would this work?

Thanks a lot guys, this forum has been great:thumbsup:

invision
08-23-2006, 03:19 AM
you can try that and also spray your plants thi will keep the humidity up or put a clear cup over the seedling and give it a light spray

KNVB
08-23-2006, 03:23 AM
Is it okay to spray directly onto the seedlings? I have been gently spraying around the stem to water them.

Anathema2121
08-23-2006, 04:32 AM
It's a plant and rain would be falling right on it so yeah, it shouldn't hurt to get them wet. If you're gonna spray directly on them you can put a very little bit of a mild detergent in the water to act as a wetting agent so the water doesn't bead up and it helps to uniformly dampen the plants. I've heard that you could burn small spots on the leaves if you have it kinda close to a bright ass light by the water droplets acting like a magnifying glass...I dunno if that shit is true though I've never had that problem.

Also, your idea about the pots of water in the room will work to raise the humidity. Thats what I did in the past anyway, and it worked for me.

invision
08-23-2006, 02:38 PM
i also heard you can burn them from the drops but i havent yet and i keep them about 6-8" from the hps light doesnt hurt to play it safe tho

phytokind
08-23-2006, 03:04 PM
Cannabis likes moist soil and low humidity. Seedlings obviously like a higher humidity, but they don't remain seedlings for very long so I wouldn't try to increase the humidity, just keep the soil nice and moist.

invision
08-23-2006, 03:08 PM
remember not too moist its harder to come back from over watering than underwatering 8 ounces of water every 4-5 days never sooner

mendokid
08-23-2006, 03:42 PM
Cannabis likes moist soil and low humidity. Seedlings obviously like a higher humidity, but they don't remain seedlings for very long so I wouldn't try to increase the humidity, just keep the soil nice and moist.

I agree a hot dry climate is optimal.

If for some reason you DO want to bring up the RH, spraying is a great way to feed them and make them happy as well. If you are worried about being too rough, get household sprayers with a fine mist setting. For seedlings, clones and young plants they are quite good.

stinkyattic
08-23-2006, 04:02 PM
Be warned that increasing humidity can increase your chances of pythium wilt fungus, damping off, which seedlings are very vulnerable to. I keep my humidity below 50% and have never seen it. Plants seem fine. They get misted with neem every day to- makes a nice shine on the leaves, acts as an anti-transpiration agent too so drier air is less of an issue.

KHAN
08-23-2006, 07:02 PM
Dont worry it'll go up as they get mature.

KNVB
08-23-2006, 08:47 PM
Yeah, I think I won't worry about RH until later. Its at about 47% right now and the soil is moist. Like you said, the RH will go up as the plants grow--that makes sense.