Leaf yellowing, suspected Magnesium or Nitrogen deficiency.

I have attached some pictures of an auto flowering low ryder #2

Since the attached photo it has progressed to affecting the entire plant, it is currently 2 weeks into flowering, was about 10 days in when I took the photo.

I suspect it is either nigrogen deficiency or magnesium, but I am confused as I have been dosing a good organic bloom fertilizer (at half doses) for 2 weeks now, but the problem has progressed.

It is definitely not heat or light damage and I don't think it's nutrient burn.

The soil used was a specialized organic mix (which even states it has little nutrients in it), without diging out the bag I can't give you much more info on the soil atm.

I have three plants and for some reason this one is affected much worse...it is further into bloom and it is in a smaller pot that the other two (the other two however are heading this way).

Any help is much appreciated.

Thanks

The above picture was taken about 3-4 days ago....It now looks like this....








My fertilizer is plant magic - oldtimers organic bloom 3-5-4

I have included a picture of one of the other plants for comparison.

looks like nitrogen def

Mg deficiency, I can see how one would think N def though. A N def. would have a more uniform yellowing of the bottom leaves with yellowing of the veins as well.
This one shows yellowing between the veins throughout the plant, which is either S or Mg in most cases.
Give it some Cal mag

Bump,

Anymore ideas anyone? My initial thought was mag deficiency...I was torn between that and nitrogen though, so I have dosed a tiny bit of epson salts and slightly raised fertilizer dosing (I was on the very low end of the scale anyway).

N DEF! but that plant is probably root bound also i would transfer it to a bigger pot and feed with high N water

its an N def for sure man dont be torn. good way to tell (rootbound will cause this too) is the lower most leaves yellow will fall off first

I would agree with the above its a N def. Here is a link that helped me out ALOT!! http://www.icmag.com/ic/showthread.php?t=11688 I found this on the RUI site under plant problems.

feed it and add some cal/mag...........cover both problems. another feed of same strength, and a dose of Mg. i...m....o

N deficiency starts low on the plant........Mg deficiency starts at the new grow tips. With the "cricklely" look of the leaves, I'd recommend 10ml cal/mag per gallon for a few waterings and then down to 5ml per gallon from there on.

cal mag away