First grow need urgent help

[xenomorph]

NEED URGENT HELP - LEAVES ARE GETTING YELLOW AND DARK SPLOTCHES APPEAR

Hi guys,

It's my first grow, so take it easy, please (I've made post in general topic but no one replies, so...)

It's been almost 38 days into flowering since 12/12 switch

Problems started to appear about 8-10 ago

I will try to give as much information as possible:

0,6x0,6 (m) grow tent
250w HPS with cooltube, active cooling
Soil in smart bag-pot
Watering once in 2-3 days
PH of water always tested - within average limits of 6-7
Keeping it at 50% humidity now, temperature 24-27c during the light phase, 21-23 during the night phase

Was not adding much of nutrients during the vegetative stage, it was feeling perfectly fine just very occasional (GHE Flora Bloom and Micro)

Almost avoided additional Phosphorus nutrition (as it was looking good), added just 1/4 of recommended dose one time 2 weeks after switch (GHE Flora Bloom)

2 days ago started to add more of GHE Flora Bloom as advised per manufacturer (I know it is General Hydroponics so might not the right choice for the soil, but had no other option)

To me it looks like Phosphorus deficiency - stems became to turn purple/red, leaves acting abnormal, even new once near the buds. Tips appear burnt, leaves are curling and yellowing both top and bottom, also these ugly spots appear

PLEASE HELP!!!

here are the pics:


Is it too bad? Will it make it through the flowering?

[PRIMO]

Hey X, if they were mine I'd flush with several gal.of P.h.ed water, In the last gal. half strength flower nutrients with some extra cal-mag Wait til the pots are light before you water again. Then feed 1/2 strength every other time.

[9fingerleafs]

hello and welcome, seems like you got it all figured out and thats what i think happened too, recently i ran out of nutrients and this happened to me too, so first the plant will make it to harvest with no issues other than a diminished harvest of what could have been. the thing you gotta take into consideration is that plants respond slowly, specially in soil, once you start seeing the leaves die off its because the deficiency has been going for weeks, and just as you get into the weeks 5 and 6 of flowering it gets worse because its when this nutrients are needed the most. one doesnt realize but during veg the plant does need good amounts of PK and stacks them up in the leaves like a reserve, if you didnt gave enough during veg once in flower deficiencies come easier, at this point i think you should keep feeding bloom for no more than two weeks and then flush, you want to stop the spreading of the dying leaves but the damage already done will not recover. next time make sure to feed very well your plant before flowering, you want dark healthy leaves that can aid the plant when nutrients are scarce. good luck my friend

[Toker1]

Burnt tips are from overfeeding. Guessing from the post, GH gave you a bum steer. They didn’t even ask about your root zone PH? That was a rookie move on their part.
PH of 7 seems high. What do the soil manufacturers recommend?
Measure the PH of your water before putting it in and then measure the run off water coming out of the bottom after watering. This will give you a good idea what your root zone PH is like.

[alltatup]

xenomorph Welcome to the forum and you don't have to worry about anyone being negative or critical; we are here to help and support each other! I'm a hydro grower, so I leave it to the soil growers to help you. But as said above, nutes are super important if you want to harvest the best buds. This might help you: https://www.growweedeasy.com/nutrients

[Colombo]

What soil are you using ? Light hight to canopy ? When you water is it always runoff or drip?

[xenomorph]

Thanks for all the replies!

I use just regular soil from supermarket for flowers with pH 5,5-6, it has perlite and other stuff. Showed itself good on veg, with absolutely no issues, even though I stressed plant pretty much with my rookie training.

So, at the run off water is 6 to 7 pH. But I hardly seen run off as the bag pot is quite big - 25 liters (aprox 6,6 gallons) and I never put more than 1,5 liters at once. So guess it is doubtful to be over watered. Roots are of close to the white color, checked that.

Lights are at 30-35 cm hight from the top of canopy now.

Buds seems to be still green now, but some of the tips look burnt

Most of the leaves at the top are utterly yellow, some becoming crispy - shall I pluck the bad ones?

[Toker1]

I have never used citric acid powder before. I assume so, because citric acid from lemons I have used before. But might want to check on someone that has tried this first.
You should contact the soil manufacturer and see what they recommend for PH. The soil I use is Fox Farm and they suggest 6.3-6.8 for PH. Hope that helps.

[xenomorph]

Did not really realized it has to be that precise! (6.3-6.8)

The soil I use was just no-name one from OBI market. It is sort of hard to get specially dedicated soil where I am conducting my green experiments. So this soil producers do not suggest anything for watering and pH rates.

[Toker1]

Hmm. Did you try flushing? Might help.

[Colombo]

Who makes the soil you are using. Does your soil have any nutes already in it ?

[xenomorph]

Just no name soil from OBI market. It had some basic nutes (N-P-K) complex as any soil should have (correct me if I am wrong) but nothing above that. I will not recall exact ratio, but N was little higher than P & K

[Colombo]

Hey xenomorph, Normally potting soil with nutes are designed to release over time to feed up to 3 months before you would have to feed all depending on plant uptake. Usually high in N which makes for rapid growth in veg. Adding nutes to the existing nutes (Nute Burn) builds up over time because the plant cannot absorb it and locks out other nutes from being absorbed. If your plant was doing fine before adding the GH nutes there lies your problem, Overload. They have organic soils with no nutes. I am using 2 at this time( 4 clones in Just Natural organic garden soil and A mystery seed in MG Natures Care Organic Garden Soi With Root trients to to pick the better of the two and just add water, tap or rain.I like the MG so far! Back to your problem. Personally I would Flush it with 6.5 ph tap water till the run off is 6.5 ph getting rid of the excess salts. Then when watering just water and let the plant recover. Some leaves might come back some won't. Trim the leaves that are dead and curling and Trim some of the big fan leaves that are yellow while it is already stressed No more then 20%. when it recovers, trim a few (2-3) ever other day until satisfied with the canopy or up to harvest (just trimmed some today). Given time, Your bud will finish and still be good smoke as MJ is a plant that just keeps on going. Good Luck ! Just my thoughts !

[xenomorph]

So I found the name of the soil and its nutes profile:

АSB-Greenworld
N 150-300 mg/litre
P (Р2О5) 120-250 mg/litre
K (К2О) 150-300 mg/litre
and РН 5,5 - 6,0 like I said before

Does it mean that with such profile there is no need in nutes at all?

Regarding flushing - PRIMO said above that several gal of flushing would do...does it mean at once? won't it be severe overwatering then? Also, where do I put all the run off, the plant is attached to scrog and I can not move it out of the tent. How to make flush properly?

Also, I've got some molasses here, shall I add it in the watering or not? What would you recommend?

[Colombo]

TheGrowersChoice_CanUSA.pdf Hello X ! Here is some info to read Better Crops 2011-2 p27.pdf is a chart to help understand PH. Your soil is peat which is acidic and has an additive + some lime and dolimite. I do see added nutes. It is buffered 5.0-6.0. At this stage I would Flush with 7.0 ph water till runoff is 6.8, it will try to buffer down.Then give it a water with Molasses (4 table spoons) and continue this till it recovers. The leaves may not come back to green but watch any new growth and the buds to verify it is recovering. no more nutes. peat-moss-information.htm, More info. I don' know which one but they all have nutes. You are at the ending stage of your grow and and should be happy you hav gotten to hear. You will harvest, and that's a good thing !! OH, use a 5 gal wet vac to suck up the water as you flush (I use a 2.5 gal wet vac) it works the best when you cannot move you grow. I hope this all helps, I know I have learned a lot from doing research on your problem. Go organic if you like growing in soil, just add water !

[xenomorph]

Thank you for advice and researches made - I am trying it all out now!

Just want to clarify: was it my mistake to add ANY nutes in this kind of soil?or in soil at all?

Also, for example, if soil is acidic, as mine cuz it is mainly peat-moss and water from tap generally around 7 pH, does it mean it will be balanced in the root zone and there is no much need for any adjustments? (With monitoring the run off of course)

[Colombo]

HI xenomorph, It's called a common mistake among new growers and those not familiar with their soil characteristics. I've done it myself LOL It's also a learning experience. True organic soil adjusts itself all the time because it is alive with microbes and material that constantly break down to feed the plant. Some soil that is not all organic/alive has added nutes that desolve over time to feed (usually up to 3 months, veg stage) the plant and it usually has a buffer that it usually adjusts at a ph of 7. When you add more nutes it creates what is called hot soil due to nute overload and salts buildup. This stresses out the root zone and causes lock out as too much of one nute Locks out another. Your soil has the added nutes that feed 3 months if used alone but if you add perlite it diminishes the time slightly. When your plant is in flower, only add nutes if your plants tell you ( Look like they need food) at which time you would give half nutes feed only when needed. As when watering, you just add tap water (has micro nutes) no ph ing needed at this stage. When you get to flower and the nutes are needed Ph at 6.5 till harvest JUST ADD WATER unless your plants says different. Hope it helps, Good Growing !!