Problems while flowering.

Hey guys first grow here. I have had heaps of problems along the way (fungus gnats, thrips, nutrient deficiency, light burn) and I've tried my best to fix them as I go.

However I'm 4 weeks into flower and my plants are losing a lot of fan leaves. They are turning yellow almost overnight and dying off.

I'm growing in soil, using a hlg 550 and growing northern lights. The nutrients I am using are general hydro.

I have been watering at around 6.3 but noticed a magnesium deficiency so have tried to up the ph to 6.8 and add cal mag.

Any suggestions?

Ph problems have led to nute lockout, I think.

Add earthworm castings as a top dressing.

Looks like Nitrogen deficiency the way the leaves are yellowing from the bottom up.

Give the details on your soil and exactly what you're feeding, how often, how long you've been feeding it, etc.

Typically as your plants get later into flower you will get yellowing in the lower leaves as the plant starts to pull nitrogen from them for bud formation. It’s actually a good sign that tells you that your plant is progressing properly.

It’s when the yellowing starts in some of the upper leaves that you have to diagnose which issue it could be.

I topdress my girls at 2 and 4 weeks of flower with fresh ewc. This run I will also topdress at 6 weeks. They love it!!

Kkt3 is spot on, your plants look healthy, if your concerned you could add a little more nitrogen to the mix. So that would be the green stuff with GH

If I was you I would pinch off those lower buds and anything not getting good light, those are "suckers" and will take up nutrients but never turn into decent bud

IF it was ph you would have purple hard woody stems which i dont see happening Yellowing leaves is normal but not like that. That looks like good old fashioned nitrogen deficiency calmag deficiency looks like rust spots on leaves and purple veins i would say nitrogen deficiency
if your going to use gh uggghhh use flora nova bloom only 7ml per gallon with 3ml calmag per gallon adjust ph 5.8 hydro 6.5 dirt and water

If you do have hard purple stems i cant see then that changes things

Nutrients could be low esp mag but i have to ask do you have a good breeze blowing at them with a rotating fan? Airflow is easy to forget about during the first grow.

ComfortCreator said:

Nutrients could be low esp mag but i have to ask do you have a good breeze blowing at them with a rotating fan? Airflow is easy to forget about during the first grow.

Click to expand...

Yep I have a small grow fan blowing through them.

IlliniMediCrop said:

IF it was ph you would have purple hard woody stems which i dont see happening Yellowing leaves is normal but not like that. That looks like good old fashioned nitrogen deficiency calmag deficiency looks like rust spots on leaves and purple veins i would say nitrogen deficiency
if your going to use gh uggghhh use flora nova bloom only 7ml per gallon with 3ml calmag per gallon adjust ph 5.8 hydro 6.5 dirt and water

If you do have hard purple stems i cant see then that changes things

Click to expand...

Is this what you mean? Because they look pretty purple to me.

I'd just remove the yellow leaves, add a handful of earthworm castings to topdress next time you water. Don't remove healthy leaves you barely have any. It will probably recover. Castings will improve nutrient uptake and its a super soil, will help with many issues.

I think I see multiple issues going on i'm not sure. When your leaves start to yellow from the leaf tip to vein, that's nitrogen deficiency.
The bottom leaves will be affected first, your leaf tips will yellow and the veins will be more green and the leaves will start to die off from the bottom up as the plant buffers itself with the nutrients from the leaves. Eventually the whole plant will yellow.
When you have very purple stems and also yellow leaves, it's a sign of CalMag deficiency.
Here's my advice, thought it may be a little late, here is my recommendation for next time.
You're going to want to give your plants the minimum amount of CalMag all the way from the time they get transplanted until the time you start to flush. You also want to give them Grow (Nitrogen) From the time they are adjusted to transplanting, until they buds develop in flower. And here is where I think your issue is, When you flower, they still grow for another 2 weeks or so. For this reason here is what you do, Keep feeding veg nutes until you start to see buds developing then transition to bloom nutes. That will allow the plant to stay green throughout flower until the final weeks.
You don't really want to be giving them nitrogen much if at all when they are that late into the stage of flower, they should have enough left over from previous feedings to keep them green throughout.
Definitely give them some CalMag until the time you flush. Whether you want to give them a very small dose of nitrogen to green them is up to you probably would not hurt but you don't really want to be doing that this late into flower.
Also, it's completely normal for plants to yellow and lose leaves but this normally happens at the very late stages of flowering as they are finishing off.