Does this plant have some kind of nutrient deficiency? Yellowing first true leaves

[bluter]

Yes, the first point I agree with. The question is why did it happen?

In addition, we established the second point three days ago, at which point I took actions that seem to be paying off (general application of nutes, with extra calmag way above and beyond the recommendations by Remo Nutrients, and now still above but backing off a bit back to recommended levels).

did you build the soil or purchase it? if you are in a true super soli or LOS the only thing you add to grow is water. you don't feed those soils. makes me wonder what you are in reality doing.

So, "is underfed" I think time will tell. I agree it "was underfed".

it looks to be continuing. in soilless you should see a marked improvement within 24-48 hrs. i'm not seeing that. soilless runs quick.

what is your soilless - coco? if you are feeding them all the same it won't work.

I find light stress plausible because of the coincidence of when the browning happened to all plants at the same time (increase in lighting) and then seemed to stop at the same time (when the lights were dialed back).

it's definitley not light stress. the plants don't show anything associated with it.

dialing the light back just slows everything down including development. it's not actually fixing anything. long term it can result in weak weed.

it's ok to dial it back while fixing an issue. what you really want is running the plants at the right balance with as much light as they can take. light is the number one most important factor, followed by nute levels and environment.

good news is they really aren't too bad and should fix up nice.

 

[zuraya]

did you build the soil or purchase it? if you are in a true super soli or LOS the only thing you add to grow is water. you don't feed those soils. makes me wonder what you are in reality doing.

I get the impression you haven't read some of my previous posts in this thread.

As I've mentioned before, I built the soil.

I have eight 67L boxes of worm composting that I fill only with scraps of organic food that I buy or that I get from my local organic food shop, plus leaves I pick up from the ground at a local forest.

I periodically harvest the compost, put it in breathable bags and leave it be for months.

At some point, when I need it, I put it through a sieve, take out most remaining worms so they don't die in the sieving process, and the compost is ready to use.

I mix equal parts compost, perlite, and coco coir and then measure the pH.

If I need to adjust the pH I take steps to do so (usually it is a case of wanting more acidity, so I mix with either a previous batch of soil with perfect pH or I use more coco coir, or (best option) I use compost formed with only leaves (ie carbon), which tends to be quite acid (in the 5s).

This is the soil I planted my cannabis in.

I don't feed this soil, as I've mentioned multiple times.

it looks to be continuing. in soilless you should see a marked improvement within 24-48 hrs. i'm not seeing that. soilless runs quick.

As I mentioned previously, the improvement in the symptoms I reported was noticeable after 48h, and the soilless medium is coco + perlite at 70/30 ratio.

it's definitley not light stress. the plants don't show anything associated with it.

This is just an objectively false statement.

I can definitely say I have firsthand experience with light stress in cannabis plants, especially young cannabis plants (you can find out why in previous posts in this thread).

Brown leaves turning upward definitely happens when the lights are too strong.

Now, the presence of brown tips curling upwards does not imply light stress. (we can't affirm the consequent).

All I am saying is that light stress is definitely in the realm of possibility, which is something you are denying.

And once again: all the three plants got brown tips at the same exact time and for the exact same duration, even though two are in supersoil and one is in soilless. The exact time was the 24h during which I increased the light intensity to 80% of max power.

Here are pictures now after about 96h

Here are some different leaves, first the topmost ones and moving down the plant

The discoloration that I think we've all agreed was magnesium deficiency seems to have abated.

Whatever the cause of brown tips, they seem to have stabilized in this plant (as I mentioned two days ago).

 

[Azimuth]

Your magnesium issue could very well be a lack of calcium so beware of chasing one specific issue.

 

[bluter]

slight tipping is ok and is a good sign when feeding nutes at decent levels without going over. it's not something you generally see in organics though. it still doesn't concern me, but i'd watch.

organics usually stay uniform, without showing much, if any issues. you're really not far off. i'm not sure you have enough though to make it all the way with the vermiposting alone.

that and organic mixes usually require a lot of media and big pots unless feeding.

 

[zuraya]

Your magnesium issue could very well be a lack of calcium so beware of chasing one specific issue.

I added calmag, so I imagine that I was helping either issue.

 

[Azimuth]

A lack of calcium will cause the magnesium to bind up the nitrogen causing all sorts of issues, so calcium is often a good place to start to resolve so many other perceived deficiencies.

 

[zuraya]

Today is day 30 of my grow.

As far as I can tell, my plants are pretty much thriving right now. It's amazing.

They just went through a growth spurt.

I have a question about pot size.

I think I will veg for like six weeks (at that point the plants would be eight weeks old since planting seedling into soil).

Is 5.27 gallon a good final pot size?

Plant 1 (supersoil) is in a 1.56 gallon (7.1lL) pot. I read about the rule of thumb that says that when the canopy reaches the width of the pot then one should transplant. However, that is true for just the first transplant from a cup right?

In any case, this plant needs to be transplanted again at some point (it was transplanted from initial cup about 13 days ago).

Plant 2 (supersoil) is in a 5.27 gallon (24L) pot (also transplanted from initial cup 13 days ago).

Plant 3 (soilless, coco coir + perlite, Remo Nutrients) is in a 3.7 gallon (17L) pot (transplanted about 10 days ago from initial cup).

 

[bluter]

5gal is a pretty standard size. it will depend somewhat on media, but it's used for a lot of grows.

 

[zuraya]

I have a new issue with the leaves of one of my three plants. There are small yellow/white "dots" (they're not quite round dots, but rather like deformed dots) on a small number of leaves. Some of the dots are actual holes.

After a quick search, my only suspicion is... thrips. I don't see any bugs anywhere though.

To recap:

Plant 1 is in supersoil, recently did second transplant to final 5.27 gallon pot.

Plant 2 is in supersoil, single transplant to 5.27 gallon pot two weeks ago.

Plant 3 is soilless. Coco coir + perlite. Fed with remo nutrients.

Plants are on day 33.

The photos above are from the plant on the bottom left below

It is quite bushy. I topped it (and also plant 2 on the right) and have been using gardening wire to bend the plants (especially plant 2 which has slightly longer branches that I can bend over to the side to expose the undergrowth in the middle of the plant.

Top left is the soilless, which I only topped recently (later than the other two, perhaps at the 7th node). Much less bushy.

So bushy are the two supersoil ones that I've had to make little toothpick contraptions to prevent some leaves from touching the medium.

But the main issue right now are these "dots" on the leaves. What are they?

 

[bluter]

there's a thrip on the top leaf in the first pic.

 

[zuraya]

there's a thrip on the top leaf in the first pic.

I don't think so.

It looks like a little white thrip, but it is actually just another "dot" but in the shape of a thrip. I checked the entire plant as best I could. I don't find anything moving or that looks like it is alive.

I see some red very small "entities" that look like grains of sand. There are occasionally some silvery shiny spots with black dots on them (from what I read the black dots are thrip poop).

Today I checked again, didn't find any thrips performing their acts of vandalism.

 

[zuraya]

Maybe I am mistaken about what I should be looking for. Are thrips located inside the leaf? I was looking for anything on the leaf surface or underneath. Are they actually burrowed in the leaf?

 

[Azimuth]

The immature ones look like miniature grains of rice and the adults have wings. They leave silvery spots on the leaves where they feed. They don't burrow into the leaf but are surface dwellers.

 

[zuraya]

The immature ones look like miniature grains of rice and the adults have wings. They leave silvery spots on the leaves where they feed. They don't burrow into the leaf but are surface dwellers.

Yeah that's what I thought. I haven't been able to spot even one little critter. I now recall having seen the adult version in the past, but before I saw the spots on the leaves. I haven't seen any actual bug on the leaves only silvery spots and poop spots.

 

[zuraya]

Here are some updates on this grow. Today is day 41 since germinated seeds were placed in soil.

1) I noticed what looked like fungus gnat on one of the plants (Plant 1, supersoil) exactly a week ago, two days after I transplanted to a larger pot. They have gone away almost completely. My suspicion is that they came in the compost that I used to make the soil for the transplant. The compost had not been left to sit for very long and was still moist. It might have been some larvae in it.

2) Thrips I posted about on this same Plant 1 a week ago (though truth be told they were there before that) seem to have abated. I don't see any new dots on the leaves or the silvery regions with black spots.

What I did was to let the soil dry out more than usual, by leaving without watering for longer, and directing a fan at the plant's soil, plus just observing the plant more closely and removing any suspicious "things" on leaves. I also vacuumed the grow tent. There were some bugs living under the removable floor layer of the tent.

3) Plant 2 (supersoil, single transplant at 17days to final 5.27 gallon pot) is absolutely thriving and so is Plant 3 (soilless, coco coir + perlite + Remo nutrients, single transplant at 20 days to 4.5 gallon pot).

The leaves on these plants look essentially flawless and they are growing at a very high rate.

4) Plant 1 (supersoil, transplant at 17 days to 1.8 gallon pot, transplant at 32 days to final 5.27 gallon pot) has not been as successful.

At two points in time I've had more extensive browning tips on its leaves.

This plant is noticeably smaller than the others.

On the other hand it is also seemingly bushier than the others, to the point where it seems to be a detriment.

Lots of the bushy undergrowth has not developed and has sort of withered away with many tiny leaves turning frail and yellow and brown down below.

I haven't been able to use LST very much because the branches have not grown very long. There are many leaves but very short branches, contributing to bushiness.

The sizes of the leaves are also small relative to the sizes on the other two plants.

On additional note is that the second transplant (a week ago) was not flawless. The soil was not as moist as I wanted (I should have watered and waited an extra day instead of just doing the transplant) and so the soil came slightly apart as I transplanted with likely damage to some roots.

It is not clear to me that there was any benefit to transplanting to 1.8 gallon versus directly to 5.27 gallon.

Here are some photos (note that I took these right after applying LST to Plant 3. The branches and leaves haven't yet turned up again to face the light so the plant looks very spread out without a canopy.

Here are all three plants, with plant 3 in front.

Here is plant 2 in front

Here is plant 1

Here is plant 3

 

[zuraya]

One question I am pondering is the following.

The two supersoil plants are now in 5.27 gallon pots. One of them (Plant 2) has been there since the first transplant, and the other (Plant 1) was transplanted first to a 1.8 gallon and then to a 5.27 gallon (just a week ago).

Plant 3 (soilless, coco coir + perlite + Remo nutrients), on the other hand, has only been transplanted once but to a 4.5 gallon pot.

Should I transplant plant 3 to a 5.27 gallon final pot? Or can I leave it in the 4.5 gallon pot without issue?

 

[Azimuth]

There's not much difference between 4.5 gallon and 5.27 so it likely won't make that much difference. Usually when we up pot it's at least a 3x move.

Also, those light spots on the lowers leaves on plants 1 looks like an early K ask, so watch it to be sure it doesn't spread.

 

[zuraya]

There's not much difference between 4.5 gallon and 5.27 so it likely won't make that much difference. Usually when we up pot it's at least a 3x move.

Also, those light spots on the lowers leaves on plants 1 looks like an early K ask, so watch it to be sure it doesn't spread.

I will be watching plant 1 for sure.

I have another question. I see that some people veg for only 4 weeks, then do like a 2-week pre-flower (not sure what this means, but saw it on the chart for my nutrients, and then like 8 weeks of flowering.

Right now I am at six weeks total, and I guess that is four weeks of veg.

Given the photos above, would I be already ready to start thinking about flipping to flowering in two weeks?

 

[Azimuth]

I have another question. I see that some people veg for only 4 weeks, then do like a 2-week pre-flower (not sure what this means, but saw it on the chart for my nutrients, and then like 8 weeks of flowering.

Pre-flowers are an early sign of sexual maturity but I think you're probably referring to the two week transition phase after a photo period plant has been flipped to flower. That's a period of intense hormonal changes for the plant and it starts needing less N and more P and K but especially K.

Given the photos above, would I be already ready to start thinking about flipping to flowering in two weeks?

When to flip a photo period plant depends on several factors. A bigger plant/root ball generally means more and bigger buds so many growers like to maximize their possibilities but keep in mind that the plant will typically stretch 2-3x after you flip so that height needs to be accounted for to make sure the plant doesn't grow into the lights.

 

[zuraya]

Okay, so one of the plants clearly has problems and I would greatly appreciate help in trying to treat it.

The plant in question is Plant 1.

Let me recall the details of how this plant was grown

- germinated seed planted in a cup of supersoil + perlite + coco-coir, transplanted to 1.8 gallon pot at 17 days, transplanted again to 5.27 gallon pot at 32 days.

- today is exactly six weeks after planting in soil.

Now let me go over the growing list of problems

1) Extensive browning of leaves.

At about 21 or 22 days, something happened that browned leaves on all my plants at once. It was the same day I turned up the lights to 80% of their power. I turned it back down after 24h, and the browning stopped. So, my conclusion is that it was light stress.

This accounts for only a minor part of the brown that can be seen on lower leaves in photos below (the other two plants at this point have no additional browning whatsoever).

But the leaves of plant 1 have continued to brown around the edges.

The plant is very, very bushy and short. The branches don't grow very long. Most of the undergrowth has brown tips, is frail and just unsightly.

I don't know if lack of light (which is definitely an issue given the bushiness) can make such leaves wither away like that.

I ended up removing most of the very small browned leaves in the undergrowth.

Here are examples (note that what I removed were not leaves as shown below, but rather way, way smaller leaves just coming off of a node but withering away)

2) Thrips

At around 33 or 34 days, I noticed white dots on leaves, silvery spots, and black dots (see previous posts). After researching a bit, I suspected thrips, though to this day I haven't been able to spot a single thrip.

The thrips symptoms seem to have abated (I think). It doesn't seem to be affecting more leaves and I especially don't seem to see new silvery spots and black dots anymore.

3) Fungus Gnats

Though I only noticed a few days later at like 35 days or so, I noticed the runoff from watering this plant had hundreds of what looked like tiny flies, dead or semi-dead in the water of the runoff. After research, my guess was fungus gnats.

I let the soil dry out a bit more than usual, cleaned the tent (noticed some bugs beneath the removable part of the tent floor), and proceeded as usual but observing more.

There are still some flies in the runoff but way, way less, like less than a hundred today. I try to see them in the top portion of the soil but I can't see any of them.

Yesterday, I watered the plant with water containing Bacillus thuringiensis israelensis (aka what is in mosquito bits).

I put one of those yellow sticky things in the tent and it got a few of the small flies.

My suspicion is that these gnats probably came in the soil I used for transplant on day 32. That soil contained my homemade compost but it wasn't the one that had been used before. This new one had compost that was relatively new and hadn't been left to "cure" for a few months. It was still quite moist.

4) Red Stems On Newest Growth at Top Portion of Plant

I've also been noticing in the past week or so that this plant has lots of red stems at the top, unlike the other two plants.

5) Leaf-eating Caterpillar-like Bug

Finally, today I noticed like three leaves that were full of holes (see pictures below). I inspected the plant and found what looks like a caterpillar (see below), which I removed. I think it was responsible for the holes.

So anyway, my other two plants are way larger and way healthier at this point than this problematic plant.

My big huge worry is that somehow whatever pests afflict this plant move over to the other two.

I don't know if I should remove it from the grow room, or keep trying to treat it.

Here's what a view of a top part of the plant looks like