Northern Lights 24 days into flowering and leaves yellowing

Hi Folks

Well, we have nearly made it on our first grow and we have two female Northern Lights plants that are about 3 and a half feet in height. Some basic info on our grow:

Using a 250 W fluorescent light
Growing in a general purpose garden compost from B&Q
Feeding using a chem fertiliser - B&Q general puirpose plant food which has a NPK ration of 5-5-5 and contains trace minerals
Have used organic bonemeal to supplement Ph levels
Watering using boiled tap water
Lights on a 12:12 with no interruption in dark period.
Temp maintained between 65-80

We started flowering on 1 February (24 days ago) and about 10 days ago some of the leaves started turning yellow.

At first we thought it was a Nitrogen deficiency as the yellowing was spreading from the tips but now we are not sure.

Have ph tested and it would appear the ph level is a tad under 7 so that seems ok (maybe very slightly high?)

So reading through the other posts on this forum it seems we could be over nutrilising or over watering and thus locking out nutrients? Or I thought perhaps that they might be root bound?

If they are root bound would it be a bad idea to repot them whilst they are flowering?

I would be grateful for any comments or opinions - there are a number of photos below which I have just taken which might help:

What size pot are they in? I'd probably put them in something larger with some quality soil. They may be rootbound which can lead to ph issues or there could be some fert buildup in your soil causing problems.

If you are careful and use good soil they should be ok for a transplant.....better off then they are now I think.

Revised: The Complete Guide To Sick Plants,pH and Pest Troubles - PlanetGanja.com

This link has a lot of great info.

Good luck.

Thanks for your reply Weedhound.

What about just flushing them? I am worried that if I repot them it will shock them even if I am careful.

Here is a better photo which shows the whole plant and pot size: too small?

Pot looks ok, but pushing it, lol.
A 5-5-5 nute can cause problems in flowering. Way too much nitrogen. Would look into a good flowering nute. I use the Fox Farms line, but there are other quality ferts out there. Possibly easiest, is to get a 2 or 3 part nutrient system. A 'G-B-M' (Grow - Bloom - Micro) regimin can take you from start to finish.

I thought I remember Stinky Attic saying at least a gallon per foot of stem. I honestly think your plant needs more room.

Hi All

DJCBrixton you plant is looking good, its a shame they have to yellow out like that.

I personally would repot into a 5Gal bucket. I was having the same problem.
This was from advice I received here in the forum :thumbsup:

a post of mine on nitrogen deficiency
http://boards.cannabis.com/plant-pro...ient-what.html

A good guide
Marijuana Plant Abuse

My NL are 40 days into 12/12 and are nothing but buds now.
They are probably 1/2 the size of your plant.

GOOD LUCK

Thanks for your advice guys..much appreciated.

We have decided to repot them and see what their reaction is. I'll post an update in a few days or so...hopefully it will be good news!

Thanks again.