Nute problem... I think.

Right guys, need a little help, please. I have 4 sour diesel which have only just gone into flower and I'm pretty sure they're having some sort of nutrient issue.

The grow has been going OK till this point and I am still pretty happy with my girls, but I think this issue needs nipping in the bud (pun intended).

The leaves at the bottom are yellowing and dying, which I can live with to an extent, but now a lot of the newer leaves are yellowing.

My first thought was a nitrogen deficiency, some red stems indicates this also, but I am confused because I believe there to be a few signs of the opposite (dark green fan leaves, claw and possibly a touch of burn on the tips).

I now think it may be a magnesium deficiency. This might make sense as I was lowering the PH ever so slightly, which may have gone too far and blocked the magnesium.

If someone could have a glance at the pics and give me a confident diagnosis I would be very grateful.

They are under a 600W HPS. Temps from 77 to 80 roughly. They have been on 1ml BioGrow per litre every second feed until flower and now get 1ml of BioBloom and TopMax per litre also.

Also two of the girls have what I'm assuming is some sort of genetic defect where some of the leaves grow half and half. Half normal and half yellow and curled. Is this a worry?

Thanks in advance.

hi there id say that you you did over n a little and how low did you take your ph im sure calmag in soil is best absorbed around 6.2-6.5 i usually start my veg around 5.8 letting all the nitrogen and goodness in and increase through to flower letting it go to around 6.5 even 6.8 towards finish i try keep to that and usually works out great for me if u do spot an issue u can always do ur next feed a little lower if all fails just give a calmag feed or some epsom salts with just water id do just water first id ppm going in then read ur runoff should tell u what is left in ur soil u can decide then wether to continue just water with mag or epsom salts (dress ur soil) for a couple of feeds help it eat whats left in there or wether u can continue feeding as normal

Mag. deficiency.

Thanks guys. Since my feed is organic I have decided to go down the epsom salt route to rectify the issue.

My next question is: how much epsom salts per litre and how often.

Cheers.

I tried to get the PH as close to 6.5 as possible but it could be slightly more acidic or alkaline as it's just the kit where you add a few drops and check the colour change.

Ruddiger said:

I tried to get the PH as close to 6.5 as possible but it could be slightly more acidic or alkaline as it's just the kit where you add a few drops and check the colour change.

Click to expand...

then id aim more towards it being a little lower than higher if poss I would put 1 teaspoon per gallon for the first few waterings and then back off to 1/4-1/2 teaspoon per gallon towards end of flower also maybe wise to use some warm water to mix it first then apply to ur soloution i dont use it myself i use calmag but from what ive read it doesnt always dissolve easily in cold water also my other suggestion get a ph pen there so much less hassle and keep calibration fluid nearby give it a check once a month

I was going to get a pen but the guy in the shop I use said the kit was sufficient and I would be wasting money. I really fancied one too. He also said nature doesn't PH test it's water.

Ruddiger said:

I was going to get a pen but the guy in the shop I use said the kit was sufficient and I would be wasting money. I really fancied one too. He also said nature doesn't PH test it's water.

Click to expand...

he sounds like a real guru id use a different shop lol

Hi guys. So I bought some Epsom salts to treat the mag def. Thing is, there are still quite a few leaves continuing to yellow. Is this a case of the plant jettisoning the older leaves that were damaged by the mag def, or is it likely to be something more sinister?

Thanks in advance.