Humidity Problem

[hopeitworks]

This is my first grow and I am having trouble keeping the humidity down. I am growing 5 plants in a metre square bud box with 400watt HPS and am in day 35 of flowering. My problem is that I am in the UK where it is cold right now and the bud box is in an outside boiler house (no problems with smell though!), and so I have a heater in the box to keep the temps up. If I run my extractor fan it helps reduce the humidity but takes out the heat as well and the temp drops a fair bit. I have got one of those dehumidifier box things with the crystals in it but it doesnt do a damn thing! My RH is running at 70 ish unless I run the extractor but as I explained.......
Any help or advice would be appreciated!

[BrazyJay]

wow, your humidity is way too high... so i understand (im high so i dont know) u have a building outside, with a box in it? If so, do u have the heater in the building or the box?

[MightyBuddha]

You might need a 'real' dehumidifier running.

[chimera]

70% humidity, well its high, it is still ok. I had a grow were I couldn't keep the humidity below 70 till the very end and it turned out alright. Just keep an eye on it during budding and a good circulation will help.

[Homergrower]

what are your temps......
Humidity isn't too bad, MJ is a pretty durable plant that can adapt to it's conditions very well. they say Mj should be grown between 50-70%.
The 400W HPS is probably your biggest factor in the humidity, becasue of the size of the box. 400W HPS in a 1x1x1 meter box is a very small space for such a strong light.
Either increase the growing space, or change the light.

How much are the plants being watered ??? might be too much water in the area???

[hopeitworks]

Thanks for your replies guys, the box is actually 1 metre x 2 metres in height and the heater is inside the box as the outside building its in would take quite a lot of heating otherwise! Our temperatures in UK are about 4 degrees now (and can and do drop lower than that)of a night time so you can see the problem. I manage to keep the temps at about 75 - 80 degrees and about 65 -70 at night time (dark period). I am also running an oscillating fan in there which helps slightly but not a huge amount. I left the zipped door of the bud box slightly open on it last night to see if that would help but it just dropped the temps too low. I am only watering once a day now during the lights on time to see if that helps, but that isnt doing much either! I know its really important to get that humidity down especially for the last couple of weeks so I may end up having to get a proper dehumidifier to sort this problem out.

[d4nk]

Hey just wondering, is there such thing as a humidity being too LOW?? I'm growing my plants under flouros so my grow closet definately isn't hot (meaning the plants wont transpire i think). I dont have a humidity guage so I cant tell you my exact humidity.

Just curious on whether or not i should use a humidifier.

Thanks.

[Homergrower]

Originally Posted by d4nk

Hey just wondering, is there such thing as a humidity being too LOW?? I'm growing my plants under flouros so my grow closet definately isn't hot (meaning the plants wont transpire i think). I dont have a humidity guage so I cant tell you my exact humidity.

Just curious on whether or not i should use a humidifier.

Thanks.

If you don't know what your humidity is, i would be doing anything until you do .

[d4nk]

Originally Posted by Homergrower

If you don't know what your humidity is, i would be doing anything until you do .

That's not what I asked.. I am positively certain that my humidity isn't high since I keep my closet door wide open during the day.

I am only asking if there is a such thing as a humidity that is 'too low'.

[Homergrower]

Originally Posted by d4nk

That's not what I asked.. I am positively certain that my humidity isn't high since I keep my closet door wide open during the day.

I am only asking if there is a such thing as a humidity that is 'too low'.

ok then yes, your humidity can be too low, anything under 40 % is a problem...

[d4nk]

Originally Posted by Homergrower

ok then yes, your humidity can be too low, anything under 40 % is a problem...

Alright, thanks for the help. I'll be sure to invest in a hygrometer for my grow room and i'll keep my relative humidity at at least 40%.

[hopeitworks]

OK, so I went out today and bought a mini dehumidifier to try and sort this problem out. As I arrived back home I realised we had a power cut going on !! 5.5 hour without electricity and my girls had only had 5 hours of light before the entire community went dark. Needless to say, the temperature began to drop quickly and I ended up covering them in black bin liners and bringing them into the house where we have a log fire and hiding them behind the couch for fear of them seeing any light even from the fire! What a f**&$g day!! Anyway, once the electricity finally got its head together and we had light, I put em back in their box outside in the boiler house with this new dehumidifier and 3.5 hours later - its doing very little!!! The RH is down to 65 but thats about it! This SO must have happened to someone else - help me please, what did you do to cure it?????????????? Stoned and pissed off - UK!!