Help identifying problem

[FlippyNips]

I’m growing in Biobizz light mix, about 18 days since germination in a Jiffy 7 pellet.

I fed the plants for the first time 6 days ago with 150ml of a weak mix of Plant Magic Oldtimer Organic Grow 5-3-3, the instructions say 2-4ml per litre, so 0.2% - 0.4% I mixed it 0.1% because they are still young.

The Humidity is quite low 30-45% but mostly around 40%, I was watering everyday for the 4 days before I transplanted, it was very dry every time.

When I transplanted yesterday I noticed a slight discolouration on one of the leaves, some of the roots on this plant had gone slightly yellow/golden colour also. This is only happening to one plant and only one leaf, I’m hoping it’s just that I let it dry out a little too much and will be fine in a few days but because I would like some advice.

The closest I can find in pictures is pH fluctuations, I have just checked the soil pH with a rapitest type test and is showing about 6.5 the biobizz bag says it is 6.2, does that really count as a fluctuation? that is if my test is all that accurate.

Yesterday

Today

Thank you for any help.

[99PerCent]

See the slight yellowing in the root?

Is this centered around where the drainage wholes are?

If not, she has been root bound just a little to long.

What you see is the plant feeding off of the lowest set of leaves.

She is hungry for a re-pot. Rule of thumb seems to be 3x larger than prior container produces healthy green plants.

[ryasco]

That looks to be a bottom leaf so i wouldn’t worry too much. If it continues then it might be problematic. My guess is a few roots might have gotten roughed up so it borrowed some fuel from the leaf. (nitrogen., phos., potasium, etc) It doesn’t seem to be one element or an insect but hopefully somebody chimes in with a better answer.

[ryasco]

Ha! Ha! You barely beat me.

[99PerCent]

I got my six guns firing tonight.

99

[FlippyNips]

Thank you, I forgot to mention it’s the plant I pulled out the pot a couple of days prior to see if the roots were bound, probably damaged them slightly then. The yellow patches don’t really correspond to any of the drain holes, more random than that.

I’ve transplanted into pots about 2.5x the size, should I start feeding now? Most of what I have read says not to feed too soon so I’ve been putting it off apart from the one small weak feed I gave them last week. I’ve just checked the schedule on the plant magic website and it says to feed from the beginning which seams to contradict a lot of advice out there.

[99PerCent]

@FlippyNips

The yellow patches don’t really correspond to any of the drain holes, more random than that.

That is why the plant has turned to feeding on the lowest set of leaves. These yellowed roots are of no value to the plant any longer.

@FlippyNips

I’ve transplanted into pots about 2.5x the size, should I start feeding now?

No, run with straight, pH correct water at first.

Do you have kelp meal? Roots recover with tea made with kelp meal and other goodies, especially when caught early, as you have.

[FlippyNips]

I have no kelp meal, I want go get something tomorrow, should be able to get seaweed meal that is normally fed to horses, no idea if it’s kelp though.

I can get this tomorrow as the shop is local to me and the price is good https://www.onestopgrowshop.co.uk/products/plantlife-superb-kelp-250mls

What do you think?

Thanks,

[99PerCent]

That would likely be a good thing to add. Just check the label to be sure there are no surprises in there

[Mr.Sparkle]

Woah everyone, step back breath and think.

First what are the signs?

We have lower leaf necrosis, so how does leaf necrosis happen ?

Excess or deficiencies in nutrients, which if fed too much or too little will happen, also pH lockouts can cause the same thing.

So whats the cause ?

Well the plants look “really” green but healthy otherwise and were just given there first dose of nutrients and weren’t like this before “hmmmm i say”.

Being that the plants are still early and that your biobizz looks like a pre fertilized “lite” mix which i have never used myself, but your plants were healthy and doing find on just water and look more than healthy in the pics so much so that personally i would be backing off the nutrients with how dark your plant is, i would personally say you over fed and locked/burnt the plant.

Adding anything will just cause more issues so just water for now with plain water and do so till you have slight run off, check the pH of the runoff just to be safe, but do this for the next week or so till the media lvls out and only when the plants start looking like they are needing some nutrients such as lighter green to boarderline yellowish leaves then start to add some feed back in to get nice looking leaves.

Pretty sure you just fed to heavy too soon due to the combination feed and pre fertilized mix and have started to lock the plant out either due to too much or pH.

[ganjajuana]

It looks like nutrient burn from some drops of the nute-water getting on the leaves. I have never fed a plant at 12 days from germination. I usually give my first feeding after up-potting from the cup at about 3-4 weeks. These thrifty plants have enough food stored in the cotyledon leaves to feed them the first few weeks. Always be careful not to water the leaves when watering with nutes.

Lots of good info so far. Not saying I am right here, but another angle to consider.

[Muleskinner]

have we considered the possiblity that the leaf just got mashed against the side of the container? I often get a few bottom leaves looking like that from pushing the containers toger and catching the bottom leaves between pots.

[Morgwar]

From those two pics it’s spreading and I don’t think it’s nutes. Ive seen it before and the leaf is still pliable but cracks a bit when bent, never identified it but I know it spreads slowly.
From my veggie and fruit tree experience Id call it an infection, prune it and burn it, and give her a LOW dose of aspirin (or any product to that effect) to boost the plants immune system.
Edit:
Google rust spot fungus and phosphorous deficiency.
Like everyone said above, cut back nutes plus what I mentioned. I’d also treat with neem oil foliar to cover my bases.
that leaf needs to go away!

[gordongecko]

Excess Phosphorous, agree with @Mr.Sparkle, flush em.

[FlippyNips]

Thank you for all the suggestions I’v looked at lots of photos of all the possible causes, I flushed them 2 days ago with about 1 litre water each. The fungal infection also looked like a possible cause so yesterday I pruned and just after lights out this morning I sprayed with a weak aspirin solution 75mg to 1 liter of water.

I can’t check the pH of my water or the run off I collected when I flushed until Monday but the soil is about 6.5.

Today the worst plant now looks fine but one of the others has now started to show other symptoms of what looks like nute burn the newest leaves have started to turn light green/yellow on the tips and the leaves just below have brown tips. Could I get nute burn 2 days after flushing?

Should I do anything before checking my pH on Monday? Or just wait to make sure I don’t do anything to make it worse.

[Mr.Sparkle]

very very minor on the other plant, i would just leave it as your just below that threshold were adding more of anything can cause some burn. looking healthy though.

[FlippyNips]

Just thought I would do an update on this.

There has been a massive change for the better over the last month, I think there must have been multiple issues but the biggest difference was seen after I changed the way I was watering.

When watering every other day they were drying out so much the soil would shrink to the point it would move around in the pot so I would give them a bit of water between main waterings because I was worried they were getting too dry. Once I stopped doing this and just let the soil completely dry they improved over the next 2 weeks. They were transpanted into 11 litre ( 2.75 gallon) pots 10 days and are doing very well.

It’s now 8 weeks since they sprouted, over the next week I’ll build another light fixture to add another 3 or 4 T8 tubes, build a scrog net and change to 12/12.

[99PerCent]

Classic over-watering.

They recovered just fine.

They really like T8 lights in veg, don’t they?

[FlippyNips]

I never really thought I was giving them too much water, just too frequently so they didn’t dry out enough or get enough run off.

T8’s appear perfectly good to me they certainly aren’t the tall weak leggy plants I kept reading about when I researched lighting, I used them because they were the cheapest option. I’m going to have to flower under them too, but with at least 25% more tubes, a change to mostly 2700K it should produce enough to be worth it.

I think I’ll make a T8 appreciation thread when I’ve made my new fixture, they are cheap and the heat is easily managed even with old magnetic ballasts.