Autoflower - 19 days old - Something is going on with her

[flexy123]

I am not really happy how my Autos are growing. I put the germinated seeds in soil 15 days ago:

It might just be too cool at night currently, waiting for my heating mat. IMHO my seedlings should be MUCH bigger at 15 days?
(Sorry for crappy pics). And yes I put them in the final pots on purpose, just to see how they will go.

 

[Emilya Green]

And yes I put them in the final pots on purpose, just to see how they will go.

and here you see it...

without using extraordinary watering techniques, a small plant in a large container is very very hard to water correctly.

 

[flexy123]

(Excuse me for posting here in this thread, but I have some more questions where I think we all can learn something so I don't make an extra thread...if that's ok

Emylia,

So as probably mentioned earlier I have an otherwise great "looking" and feeling soil but it has a ph of 7.3 according to the bag which is somewhat concerning me. Worse, as I probably also mentioned somewhere our water is 8.5.

The more I look at my plants and the symptoms, YELLOW leaves etc..etc..it's obvious that it's a ph problem since the plants with this higher ph cannot take up Iron, everything points to this.

My question: When I use "ph-down" with my watering (I fortunately have a bottle here), is this all I need to permanently bring the SOIL ph down...or would I also have to do something to my soil like adding organics/moss/sulfur or what they recommend to bring the ph down?

I understand that organic ph-down like using vinegar etc. only works temporary...so if the ph-down I have is non-organic, means it's permanent and the soil then stays at that ph? Basically I bring my water down to 6,2, water my pots and I don't need to bother about mixing anything into my soil?

Thanks

PS: Still baffled why this "special potting mix" they sell here with big Cannabis plants on the bag is 7.3

 

[Emilya Green]

Lately a lot of people have put a big importance on soil pH, and a perceived need to adjust it to be different than it was designed to be. Actually, your soil was designed to reside at 7.3 for a reason... to produce pH drift within your container. This is what I would call a "fast" soil. You can slow it down a bit in the future by adding sphagnum moss and such, but then you have changed the nature of the tool that you have bought for your garden, your soil. You have undone what the folks at the special potting mix laboratory thought was important, making that a fast soil. The reason for having a soil that can quickly traverse the entire usable pH range in a wet/dry cycle is obvious for a voracious grower like a weed that typically will drain a container of water in 3-4 days. It is actually desirable to start at the low end of the soil pH response chart, and let your soil and the particulates in the water drift it upward.

This drift does not happen immediately... it happens over time. If you think of the volume of water in a properly saturated root ball, compared to the volume of soil, it is clear that the pH of the incoming solution is in control of the pH, while it is there. The topsoil after it dries will revert to the 7.3 base, but below the water table line, the pH is much different, and slowly drifting upward. Over the 3 day wet/dry cycle, your entire plant's root system is able to enjoy the entire usable range of pH. It's actually a pretty cool system... why fight it?

Use it instead. I recommend adjusting your pH to 6.3 for your incoming fluids and then smile knowing that every 6 hours, you gain about a point of pH in the core of that root ball. No nute can evade this strategy.

also, adding a pH down product will not permanently change the soil.. it only adjusts the incoming fluid. It doesn't matter if you are using an organic or purely acid based pH down, both do the same thing. The only difference I have seen is that the higher priced phosphoric acid pH down solutions, actually become a nute when they break down instead of leftover chemicals in the soil.

 

[flexy123]

Which of course means I need to ignore all those posts/articles (I just saw them again) saying "don't adjust your water's ph when you grow in soil" since we want a drift from 6.3 --> 7.3.
If I were to use my water "as is" (without nutes or any ph down) the soil would drift from 8.5 --> 7.3 which is obviously (totally) wrong. And this would also explain my yellow leaves right now...

So in short: When I don't add nutes like right now (because I use pre-fertilized soil mix) and I just give water..I MUST bring the ph of the water down. (Which I don't need to do when I add nutes because this otherwise takes care of the ph)

Yes makes sense!!

 

[flexy123]

Emylia,

I totally understand this "drifting" idea of the ph and it makes sense.

However, right now it is winter and the plants use FAR less water (obviously), currently I am watering as low as maybe once a week.

So if I ph my water down to 6,3 and water, and you say the soil/water mix gains 1ph every six hours, at the end this soil will again reach/buffer to 7,3 and then stay like this for the majority of the days (until I water again, obviously).

So my thinking here whether it ultimately still would be better to get another type of soil (or mix something in my existing soil) to have the ph of the soil drop?

**
I want to add that I more and more realize how important ph is since this is really the key for proper nute intake and plant grow, the MOST important thing where everything else depends on.

I don't want to know how often I (and others) spot some deficiency, say Cal/Mag (yellow leaves etc.)..and then make the mistake of rather than addressing the root of the problem (PUN ) getting some additive like CalMag - instead of solving the problem WHY the plants cannot get enough iron/calcium.

As Emylia says "Put them in good soil, up-pot regularly and properly water at the correct pH." <--- basically covers all of how to grow the best and healthiest plants.

Additives like CalMag etc. (for Calcium/Iron) do NOT solve an existing problem, at best they can only help in an emergency, you still need to correct what's actually wrong. Worse, some could make the mistake to ignore a problem (soil, water etc.) by using additives INSTEAD (believing it is a fix) and not looking at the actual problem.

 

[Emilya Green]

Emylia,

I totally understand this "drifting" idea of the ph and it makes sense.

However, right now it is winter and the plants use FAR less water (obviously), currently I am watering as low as maybe once a week.

So if I ph my water down to 6,3 and water, and you say the soil/water mix gains 1ph every six hours, at the end this soil will again reach/buffer to 7,3 and then stay like this for the majority of the days (until I water again, obviously).

So my thinking here whether it ultimately still would be better to get another type of soil (or mix something in my existing soil) to have the ph of the soil drop?

**
I want to add that I more and more realize how important ph is since this is really the key for proper nute intake and plant grow, the MOST important thing where everything else depends on.

I don't want to know how often I (and others) spot some deficiency, say Cal/Mag (yellow leaves etc.)..and then make the mistake of rather than addressing the root of the problem (PUN ) getting some additive like CalMag - instead of solving the problem WHY the plants cannot get enough iron/calcium.

As Emylia says "Put them in good soil, up-pot regularly and properly water at the correct pH." <--- basically covers all of how to grow the best and healthiest plants.

Additives like CalMag etc. (for Calcium/Iron) do NOT solve an existing problem, at best they can only help in an emergency, you still need to correct what's actually wrong. Worse, some could make the mistake to ignore a problem (soil, water etc.) by using additives INSTEAD (believing it is a fix) and not looking at the actual problem.

Flexy,
I disagree with one thing you have said here... that because it is winter the plants are using less water.
These are weeds, growing indoors... they do not care what season it is. Water does not leave your containers and make you need to water because of ambient humidity levels, the plants either use or do not use the water. Speaking of going after the real or the perceived problem comes into play here. If your weeds are not able to drain the container they are in, in 3-4 days, something is wrong... you either have them in too big of a container or there is a root problem. The solution here is not a slower soil, it is fixing the underlying problem and developing a healthier root system.

 

[flexy123]

Emyilia,

I am basically growing outdoors, the green house is on the balcony. In summer we have horrendous temperatures, 40C (110F) easily and now at night it can get down to 7, so the temperature difference (Winter/Summer) alone is likely a reason the plants need less water. I guess the plants are also growing slower now which also makes them use less water. Summer I needed to water every day (checking weight of pots), now it takes a long time.

Anyway since I have some Autos for testing (and also some 10"-12" feminized ones) which all at this point (I think) don't need any (artificial) nutes I am using water only for them, and today I finally started to ph down my water. I will see how the plants will react. My grows (including chillies) always suffer from very pale green if not yellow leaves at some point.

Ok let me make a picture.

The left one by the way is the one I posted some weeks ago, where you said it might perhaps die due to damaged root system. (After I repotted them). So it seemed to have somewhat recovered.It's still clawing a little downwards, the right one looks far better doesn't claw down that much.

(Those are approx. 8.5" and 7.5" tall, photo makes them look bigger but those are small pots)

The other question would be about topping them (left one looks like a tree...) but that's another topic

 

[Emilya Green]

I think they are looking good, especially in the new growth, but still dealing with a bit of root problems. They are quickly recovering however and I would say that you should just keep doing what you are doing... they may look like they are growing slowly, but I think that most of the activity has been below the soil, and you just cant see it. Keep doing what you are doing, and I think your water usage will increase dramatically in another wet/dry cycle or two. I don't think this has anything to do with the season, autos can adapt to the shorter daytime out there on the balcony.

I would definitely top too... its time to stop this vertical climb and get some more tops working for you.

 

[flexy123]

Yup, looking at them in plain daylight they look better than inside the GH under the lights. And yeah I'll top them today.

 

[kwingibingi]

I just want to say that I changed my light schedule to 12/12. More trichomes are showing, buds are getting fatter (a little bit...). it seems my plant is doing kind of well anyway even though she have lost biggest leafs. I will keep her under that ligjt schedule for let say two more weeks, maybe all she needed was less light during flowering stage.
i will update with some pictures in couple of days guys!!

 

[kwingibingi]

Is it time to harvest when I see amber tricomes?
I have 10x glass which is not perfect for checking trichomes but at least I can see colors. I could see amber trichomes along wiith I would say milky ones. Seems that my buds are still getting fatter. What to do? Wait couple days or cut it off?

 

[Emilya Green]

I always shoot for 5% amber. When I see that, and no more clear trichomes, it is harvest time in my tents. Everyone has their own preferences... the more amber, the more of a body high you get. If you pull when they are all cloudy and not much amber, you get a very cerebral heady type high. When you pull should be based on your personal preferences ... there really are no rules. My first run years ago, I did a multi stage harvest, just so I could sample finished product harvested at various amber levels. I found my favorite at 5% amber. Maybe you will like 10% better, or maybe 1%.... we are all different and have different needs.

And in that last 2 weeks, while the trichomes are starting to turn, your buds will definitely be getting fatter. It seems to me that just like in the beginning of flower, there is a period of 2 weeks of stretch... I also think that the buds stretch in the last two weeks... and typically mine at least double in size, and I estimate triple in weight, during that time.

Sounds like you are very close! congratulations!

 

[flexy123]

I am needing to ask for some more help...ok pictures should be talking for themselves:

Remember, those were the plants I repotted some weeks ago and they didn't take it too well. Afterwards they recovered somewhat and then I topped them about above third/fourth node.

I did NOT feed them any nutes yet, they are in normal, pre-fertilized potting soil.
(It's likely that the potting mix is simply depleted of nutes now???)

This time I *did* ph down my water to about 6.4ish any time I watered. I also did not water them too much, in fact currently I am watering maybe once a week when the pots are really light. (I am aware the previous problems were likely not only from repotting but also from overwatering).

But I am slowly getting concerned. Am I right that the plants look VERY hungry? I want to start feeding them (and probably also give some CalMag as a an emergency treatment).

To me it looks like extreme N deficiency (???), probably also Iron. Problem: Right now the soil is still pretty moist from the watering about 2-3 days ago.
Any smart course of action here?
Should I wait 'til they're dry and then start feeding some of my nutes?
Should I foliar spray them with CalMag right now?
Or should I just leave them as they are?
(Note the plants are a little dusty from the sand that I put out in the greenhouse)

Also note the slight reddish on the leaves...

TLDR: They're not green and lush like I want it, in fact this is the problem which is plaguing me ever since, my plants ALWAYS look pale/yellowish at some point. It is driving me crazy.

 

[Emilya Green]

The red looking leaves are typical of a phosphorus deficiency. I think it is time to give her flowering nutes, the veg nutes in the soil are not cutting it. Phosphorus being a mobile nutrient, will first be cannibalized from the lower growth and will move upward until the nutritional needs are met.

 

[flexy123]

The red looking leaves are typical of a phosphorus deficiency. I think it is time to give her flowering nutes, the veg nutes in the soil are not cutting it. Phosphorus being a mobile nutrient, will first be cannibalized from the lower growth and will move upward until the nutritional needs are met.

Mind you they're not flowering, but the tip with the phosphorus def. is very valuable.

As pretty much always with nutes, I just read that phosphorus deficiency can also come from incorrect soil ph and *possibly* also because of the lower temps right now.

I think I really have to get a soil ph meter otherwise I won't get anywhere, right now I can only guess about the ph of the soil...I have no idea what this is at currently.

 

[Emilya Green]

Mind you they're not flowering, but the tip with the phosphorus def. is very valuable.

As pretty much always with nutes, I just read that phosphorus deficiency can also come from incorrect soil ph and *possibly* also because of the lower temps right now.

I think I really have to get a soil ph meter otherwise I won't get anywhere, right now I can only guess about the ph of the soil...I have no idea what this is at currently.

I did assume this is an auto... and I suspect she is switching over now, and would do so faster if she could find the phosphorus she needs.

 

[Emilya Green]

Mind you they're not flowering, but the tip with the phosphorus def. is very valuable.

As pretty much always with nutes, I just read that phosphorus deficiency can also come from incorrect soil ph and *possibly* also because of the lower temps right now.

I think I really have to get a soil ph meter otherwise I won't get anywhere, right now I can only guess about the ph of the soil...I have no idea what this is at currently.

Knowing that your soil has that strong drift is all you really need to know about your soil pH, and having a meter to show you momentary readings is a waste of money in my opinion, just make sure that the incoming fluids are adjusted correctly and you should not have a problem.

how low is your temp getting?

 

[flexy123]

Knowing that your soil has that strong drift is all you really need to know about your soil pH, and having a meter to show you momentary readings is a waste of money in my opinion, just make sure that the incoming fluids are adjusted correctly and you should not have a problem.

how low is your temp getting?

You are right, I just read about ph meters and it took 10 mins to ditch that idea

I did a VERY rudimentary test just right now (vinegar, baking soda etc.) and I got no reaction either way so I can assume the soil being neutral.

Yes, those are not autos, sorry I forgot to mention that.

While temps can get as low as into the 10Cs (50F, 52F) outside early AM I now have a heating mat in the green house. I have a temp sensor in one pot and it goes down to 17C/18C (63F), so that's the lowest soil temp I get at night currently. (Which IMHO should be "ok")
Temps in the greenhouse itself, down to 14-15 early AM, likely a little higher down where the pots and the heat mat are.

** I guess what I'll be doing just wait a few days until pots are very dry and then give "normal" vegging nutes I usually give. (I am also aware that December is not exactly the best time for growing )

 

[Emilya Green]

this is an odd one, but yeah, I think you are on to the cause... brrrr

If your vegging nutes have any sort of all purpose fert in there, there will be some phosphorus. It is going to be interesting to see what sort of fall colors you get on your plants with those cool temps.