Light brown spots on fan leaves

Hi. I have a plant that's somewhere in its 5th week, the first week of flowering. I just started noticing some light brown spots on some of the fan leaves. The plant is a really short and dense plant. I don't mean short like it looks stunted, I mean the nodes are really close together. I've looked at some of the plant problem photos that I found somewhere else, it doesn't look too much like any of them. It's in a pretty small pot so maybe being root bound can cause this? I gave it a big last dose of veg ferts a few days after I switched to 12/12 so maybe too much nitrogen is locking out something else, is that possible? The ph of the soil is ok and I fed it its first flowering ferts a couple of days ago using Fox Farm tiger bloom and big bloom. I noticed the spots before I gave flowering ferts but after the last veg fert feeding.

need pics....could be many things

It's not the best picture but it's the best I can do. My camera's on the fritz and it took me like 20 minutes just to be able to get a pic.

I had to black out some stuff in the background so don't pay attention to that.

It looks like the first signs of spidermites, just get 2 fairly wet cloths or 2 sponges and put 1 at sponge at the topside of the leaf and one below and swipe backwards.

Or ye and look underneath the leaves you might see some, even if you dont still do what i said just to be sure.

heres a link to help you http://www.youtube.com/watch?v=Z34osq5tGnY skip to 7mins and 20 secs and it shows what the problem youhave is and how to get rid of it, and i was right they are the first signs of spidermites.

get some pyrethin...
WT

that couuld be a lot of things broham. could mean you need some magnesium. if you use tap water i doubt its this because the water from your tap should have enough mg in it plus the nutes you use probably have a little too.

could mean you have spidermites (thats easy to check just look underneath the leaves). i dont know about the mites though because only that one leaf is being super manhandled. if you do have spidermites though might i recommend a hot shot no pest strip. it will take care of all of them easily, quickly, and without a mess. just hang it up and theyre gone within a couple days. on anothr note i feel like im always saying this haha. hot shot should pay me some royalties.

it could mean the radiant heat around your leaves is too much. are you using cfls around the bottom of your plant?

it could also mean you have a fluctuating pH, i bet due to a combination of possibly overferting combined with the salts fox farm leaves behind.

good luck!

ah!! using FF? well we had the same exact thing happen from over-fert, ph imbalance...got those specs all over the leaves....flushed and Ph down, and it went away...
WT

i learned the hard way too.....use FF nutes at the lowest recommended amount, and only every other feeding
WT

Chongman in your case that looks like a ph imbalance or nute lockout....just a quick guess without alot of info. :)

I don't see any mites or silk or anything anywhere. And like I said I didn't notice this until after I gave it a last big dose of FF Grow Big. I did overdose it on GB throughout veg as it seemed that it liked it.

I have 92w of CFL (in 1 rubbermaid) at the top and this leave is not really at the top. There is other foliage above it that looks good except for a part of one smaller leave that grew into one of the lights overnight. :wtf:

I have another plant in the same space that I thought was from the same bag seed but doesn't look similar at all. It's a more stretchy plant with probably 3 to 5 times the space between nodes(still not a lot of space, just the other plant has super dense nodes, I'm almost thinking lowrider?) and it seems to be doing fine. But it's in a pot that's 2 or 3 times the size of the spotty plant.

I'm like a week into 12/12 so I guess it's not a bad time to just flush and then give the beginning flowering ferts again(first feed for one of the FF ferts is bigger). The FF flowering ferts contain some nitrogen so I guess it should get everything it needs.

I'll also wipe the leaves down and maybe spray the leaves down with water daily just in case it's mites, because the water might at least keep them in check.

Oh yeah I forgot to mention that I'm using R/O filtered water.

I think it might be leaf spot fungus and if it is you don't wanna be wiping water on your leaves regularly

That's not spider mites. The blotches are WAY too large. Mite damage presents first as tiny speckles high on the plant, especially in hot grow rooms. If that were insect damage, I would lean towards thrips instead. The pic is a little blurry. Can you steady your camera better so we can get a clearer picture of the damaged leaves?

It's also not Magnesium, which presents as pale striping between the veins, in a very regular pattern that is easy to spot.

You need to be adding CalMag Plus and doing regular soil runoff pH tests if you run RO water. And you need a gallon of medium per foot of main stem. If you suspect rootbound, why are you waiting? Happy feet makes happy plants.

The plant's doing well now. That one leaf is still a bit blotchy but the plant is in the stretch and bud sites are popping up all over, no more leaves have become effected and all the new growth looks good.
The other plant started to show classic signs(I think) of nitrogen fert burn with yellowing leaves starting at the tips. So I think over ferting had something to do with the spots even though I don't know why it would be manifested as these light brownish spots.

But both plants seem to be doing really well, they are growing like crazy on about the 11th or 12th day flowering, except for the fact that I broke the main shoot! http://boards.cannabis.com/plant-pro...in-branch.html

I'm aware that foliar feeding with fertilizers have the ability to burn leaves a bit as well. Especially if they are near the lights..