Hi I am growing a red dwarf (buddha seeds), a royal dwarf (royal queen seeds) and an original amnesia (forgot already). I am into the 5th week and growth has been satisfactory. I am using a 250w cfl lamp, a heating mat, compost soil and half strength root-it feed. Entering week 3 i noticed on one of the plans slight discoloration at the tips of the lower leaves of one plant. I ignored it but after a week all plants had the same issue. Some of the lower leaves had become yellow-brown and even started curling up or down. I moved the lights up (from 4inch=10cm to double the distance) and flushed using rainwater for good measure. After the problem receded it started once again. The plants are about 5 inch high and between 2-5 of the lower leaves of each plant are a little or very affected. Temp at the base of the plant ranges from 28-30celsius in the 18hrs the light is on and 18-20 when its off. A ventilator is not installed yet but the wardrobe has no top so oxygen i presume can enter Any thoughts welcome
discolouration of leaves: pls advise
- Thread starter zakinos
- Start date
SnapsProvolone
Well-Known Member
We need pictures to really be of assistance.
Mad Hamish
Well-Known Member
No ventilation is no air flow. Your plants are definitely suffocating. Also sounds like pH is out of whack. I will need details on your soil mix too, some pics etc. But I can tell you off the bat that you need ventilation man.
Plants do not breather oxygen btw. They take in Carbon Dioxide. This is the gas they need, not oxygen. Relying on diffusion alone for your air flow is silly.
It takes investment to do this. I urge you to go read up on stealth growroom design (which is what you are dealing with).
You might get these to finish, but to do proper runs you are going to need to give better care.
Plants do not breather oxygen btw. They take in Carbon Dioxide. This is the gas they need, not oxygen. Relying on diffusion alone for your air flow is silly.
It takes investment to do this. I urge you to go read up on stealth growroom design (which is what you are dealing with).
You might get these to finish, but to do proper runs you are going to need to give better care.
SnapsProvolone
Well-Known Member
There has to be a convective flow with no top on the cab.
Mad Hamish
Well-Known Member
With the little heat off CFL's this won't be much. Not nearly adequate. I have seen so many grows go south due to this issue. Not many people realize that inadequate air flow can actually stress plants to the point of herming.
A fan is such a tiny expense that skipping sorting it our is just plain, well....
Thanx for taking the time guys. I have already bought a silent bathroom vent but when I tried to mount it I realised it is broken and now I wait for a replacement. Soil is standard outdoor plant compost mix from a local hardware shop. My ph meter is also missing in action so I try to give them rainwater or at worse water from a reverse osmosis filter. I live in a remote island so supplies are an issue - at best they take 2-3 weeks to get here.... Here are some pics
TopProspect
Member
You said you had your lights 4 inches away but then you doubled the distance to make it 8 inches away from the plant? If I'm understanding correctly you should have your lights closer. CFLs have weak light penetration, so at 8 inches away they're doing very little other than stretching your plant. Generally you want your CFLs as close as possible (2-3 inches away). Invest in a cheap oscillating fan as well. It will help with the air flow and make the stems of your plants stronger. The PH level could defiantly be the problem, so check that out for sure. Pictures will defiantly give people a better idea of what's wrong.
here are the pics. In one of them u can see the temporary setup until my bathroom vent is fixed. Oscillating fan blows from a few feet away and there is a small gap at the top of the cabinet. 
The front from where the fan blows is 90% closed with a sheet of mylar (left it wide open for the pic) so there is some breeze from below which comes out from the gap at the top.
The front from where the fan blows is 90% closed with a sheet of mylar (left it wide open for the pic) so there is some breeze from below which comes out from the gap at the top.
SnapsProvolone
Well-Known Member
They look good. Baby leaves do that. If it's not progressing up the plant your fine. Those baby leaves will roast off normally. All looks well. 