...how to control humidity. Can someone enlighten me please? From what I understand if there's not enough simply add moisture by spray or what have you. could you simply set a cup of water in with the plant to raise the humidity?
Most people usually say humidity is not a very big factor to worry about when you just start out... 30%-50% is said to be ideal if i've researched right. As to how to control it (raise it I'm assuming) use a humidifier thats the best option. If you can't for whatever reason alot of people say they control theirs by misting the foilage and it keeps it stable, I personally use the cup of water, however the more surface area of water you have to evaporate the more humidity you get Solo cups are not ideal but brought mine up 5% use a small tub or large sided pan if you can... If you have future problems tho I would just buy a cheap humidifier a gallon size one and keep it on a 15 min or so timer
I have a Holmes Cool Mist humidifier and it only adds about 10% to my box (from 20% RH to 30%). Not really sure why that is though, you would think it would need to more than that to keep a room humidified. I tried a pan of water. I got a pan that was all black in color thinking it would heat up from the lights and help the water evaporate faster. It maybe raised the humidity 5%. I've heard of people sitting a pan of water on a heating pad. I haven't tried it, but it seems like intentionally dumping more heat into the box is counter productive. There are also warm mist humidifiers. Again it seems like adding heat is counter productive. The difference between warm mist and cool mist humidifiers in that the warm mist ones use heat to generate steam, the cool mist use a wick pad that sits half way in the water, then suck air through the non-submerged side of the pad to generate the "mist". The cool mist actually work like a swamp cooler AC unit and mine dropped my temps enough that I was able to add two more 27 watt CFLs without raising my temp. But I have to keep a close eye on the water level because when it dries out, the temps jump back up pretty quickly. The warm mist ones are much more effective. I've heard not to spray water directly on your leaves because it can act like a lens and cause a hot spot that burns the leaf. I have a couple of spots on a couple of my leaves that might be from where a drop of water sat after watering, but it would be something else too. Also, maybe a warm mist humidifier outside of the box, near your intake, might add significant humidity without adding too much heat.
nice, appreciate the help guys. I have another question. A ppm measures waste in the water right? if not what would i use this for and how do i fix the problem? Is it necessary if i change out my water every 10 days anyway?
I believe that a PPM meter measures the Ph content of your soil (at least everytime someone bashes on my Ferry & morse PH meter they reccomend getting a PPM as for your water I'm not sure what you mean unless your talking hydro and Im a soil grower so...
BTW yes foilage spray does cause hot spots if sprayed and then left under lamps if you do a foliar spray do it out from under the lights and let your plants rest from under the lights till the moisture is gone... and as for heat and water being counter productive heat and water make humidity. So there for increasing the heat applied to the water would create more humidity.