Finicky Sativa Issues - Droopy leaves and yellowing

[skillz]

Hello all -

I have some issues with some droopy plants, turning lighter green and yellowing lower leaves.

background:
Plants under 100w LED bar
Temp - day 80 - Night 70 - Humidity 45 - 60 %
Karma haze (top dawg seeds - its an (NL#5xHaze) x A5 Haze @ 36 days
Plagron Allmix soil (they were started in root riot plug --> 1litre biobizz lightmix --> now in 1gallon (3.6litre) Plagron Allmix (organic enriched soil) --- some clawing leaf tips when they went into the Allmix...
Using tap water which comes out around PH8 - I use citric acid to bring own PH to 6.3 - 6.9 after nutes are added

I did 2 feeds with Alg-a-mic after hoping this helps plants deal with toxicity/stress...
Sprayed 3 times with Neem since planting

I thought it could be over-watering so have been making sure to let the pots get very light / dry between watering...

The lower leaves continued to fade to yellow so I figured I could give a 1ml/l dose of BioBizz FishMix and 1ml/l BioHeaven -- not seeming to help...

I have some other plants vegging under the exact same conditions that are looking very healthy (Bog Bubble and TH Seeds Gelato33 x Bday Cake) -

As you can see some of them are looking worse than others...

 

[FletchF.Fletch]

Sometimes the Neem can affect the leaves adversely if it's mixed too strong or applied while the lights are on.

 

[FletchF.Fletch]

Do you use an ec meter to measure the strength of your solutions going in, and the runoff draining out?

 

[skillz]

Neem has been applied just after lights out... and I've followed recommended dosage of about 5ml/l -

I do not measure EC as I'm using BioBizz line (organic) - so from what I've researched EC measurements are useless for organic nutes....

I just had a look with a cheap 60 - 100x scope and I see tons of clear spheres that I thought at first were possibly eggs - but they're clear and after further research I think they are more likely to be capitate sessile trichomes ---

https://dutch-passion.com/en/blog/what-are-cannabis-trichomes-and-how-do-they-affect-your-smoke-n986

 

[skillz]

theres an OK photo if you scroll down on this link of what I'm talking about...

https://2fast4buds.com/news/what-are-trichomes-and-their-importance

 

[FletchF.Fletch]

Regular monitoring of ec is helpful even when growing organically. What happens often is that the plant doesn't use all the nutes going in, and we don't water when it doesn't need it so the buildup doesn't flush away. Then over time, anywhere from a number of weeks - 2 months that builup of unused nutes causes the soil to acidify and lockout available nutrients. This is most often misdiagnosed as a deficiency, leading to more feeding which makes the problem worse. That is why checking your runoff ph and ec is so important. It confirms that you're on the right track, and can alert you to a problem before it manifests as leaf issues.

 

[FletchF.Fletch]

Also, I stopped using Neem altogether 10 years ago or more because it can hurt the leaves. I like Captain Jack's Dead Bug concentrate. It works on everything but Aphids, will not burn leaves, and helps prevent and kill Powdery Mildew.

 

[prune]

It's Calcium you need, something fast acting but it's a little late for standard CalMag products. Liquid bone meal would be good and will help with the Phosphorus deficiency that will be next on your list...

 

[skillz]

Thanks for the feedback


Forgot to mention that I have added CalMag in feedings several times at a low dose of around 0.1 - 0.3ml/L --- its ATA CalMag...

I also realized that I had similar issues last time before transplanting... I think it may simply be an issue of the plants getting rootbound... check it out...

I'm hoping this will be a quick fix and will wait a few days before to see results before buying an EC meter... I'd rather keep things simple and am extremely strapped for cash at the moment. Âlso I have seen countless organic growers get great results without ever using EC meter

 

[VerdantGreen]

looks like you have found the problem. Rootbinding is always the first thing to look for in soil, and often the solution.


VG

 

[skillz]

So can you explain why this is more of an issue in soil than in coco for example?

I've seen others grow with 2 gallon pots through flower in coco with no problems and the medium looks even more rootbound than in my pics.. Is there a reason why roots need more space in soil?

Also - these plants won't be able to get into the flower tent for other 4 weeks --- I am transplanting into 3 gallon fabric pots (they fit closer to 3.5 gallons imo). Do you think this will be big enough to finish flowering in? (80 - 95 days flower) ---
From what I've read the roots don't develop too much more when in flowering and also fabric pots are a lot less susceptible to issues with root-binding...

 

[VerdantGreen]

Coco is essentially a hydro medium for the roots.. whearas organic soil mostly requires the roots to be in contact with the soil to extract nutrients (beyond any available nutes in the feed solution) so lots of roots at the bottom of the pot in contact with each other rather than soil means that they can't do their job.
the fabric pots should be ok.roots grow through flower but as long as they have a bit of space at flip they should be ok
.. but you are going to struggle waiting 4 weeks for transplant...you may need to do an intermediate repot .

or a more drastic solution. prune the tops by half... cut half of the rootball off the 4 sides and bottom, repot in the same pot with fresh soil.. and then you have bought some time for them to grow back in the next 4 weeks!


VG

 

[skillz]

Unfortunately I already transplanted about half of them into the 3 gallon fabric pots - the ones that were in need of a watering today... I did some more topping as well but no root pruning...
I will be able to harvest some of the plants in the flower tent in just about 2 weeks - so maybe I will send the ones I repotted today in to flower early..
I currently don't have room in my veg tent for anything bigger than the 3 gallon pots at the moment... so I'll repot the others into 3 gallons and do a bit of root pruning... I'm a bit scared to prune roots when the plants are looking so droopy... Would it maybe better to prune roots at this transplant and wait a bit before the topping to reduce stress?

 

[VerdantGreen]

i think the droop is the plants trying to get less light because they can't get the nutes from the soil to use the light for plant processes such as growth. As long as the soil is moist you should be fine... maybe don't put them too close to the light for a couple of days.
you may get away with the ones you have transplanted if you can get them into the flower tent a bit sooner, in 1 or 2 weeks.


i have the same problem with lack of space... you need to improve the logistics so the plants aren't stalling as the wait for space.


VG

 

[skillz]

thanks Verdant Green --
ya I definitely need to improve my logistics/planning... In future grows I will not have so many plants as I'll be using clones - I've taken cuttings and will select mothers ... So my veg tent is extra cramped while I hold on to all the cuttings before I can make the selection...

My first run (currently in flower) were BogBubble and they were quite slow in veg - they barely got to 12inches in height after 7 week veg (topped into 4 cola plants) and they barely stretched in flower... So I figured I would germinate earlier to allow for 8 weeks of veg for this batch with the KarmaHaze... I know some people recommend very short veg times for sativas - but I needed to veg long enough to take cuttings - and I wanted to LST/Top to try and mitigate the stretch...

 

[VerdantGreen]

yeah, it gets complicated... but as you say it is easier when using clones.


good luck with it.


VG