Severe drooping

[Frank56]

Hi guys,

-Problem:
So, over the past week or so, I've noticed some strange behaviour that I've not seen before with my plant. The plant, after watering, seems to droop heavily for 12+ hours, before coming back to life at lights on, as you'd expect at typical lights on. 12+ hours of drooping, in my experience, seems a bit excessive after a watering. I water her midday (relative to her schedule).

-Medium/grow method:
Soil: 70% BioBizz Light Mix and 30% perlite.

-Feed and supplements used:
BioBizz range (only including what I've used so far - no bloom nutes yet):
- BioBizz grow: Fed at 1/8th strength twice a week (1 litre of water per feed).
- BioBizz Alg-A-Mic: 1ml per litre: The issue started after the first time I including this in my nute solution.
- BioBizz CalMag - 0.2ml per litre every watering.

One imporant point to note is that I have given this plant barely any nutrients at all, she just doesn't seem to be asking for them.

Plant is on a wet dry cycle and I weigh the pot, so I know when she is really dry (1.7kg is a dry pot for me) - she gets either 1l or 1.5l when the pot hits this weight. I have not had any issues up until this week with giving this amount of water to her.

-Water source:
Tap water with PH of 7.2 (not dechlorinated). Extremely soft water (50 ppm, but not using synthetics so salt build up is not an issue). Water is not PHed as I am running in a good soil. Runoff PH is about 6.5, which is spot on.

-Strain and age
Fast Buds Cream Cookies
~35 days since sprout.

-Climate:
It has been pretty hot this week, but running in a cabinet that holds between around 25c and 28c with 50-60% RH (lowered from 70-75% due to starting to flower).

- Light used:
1x MarsHydro TS1000 between 20-24" on 75% power.
20/4 schedule

-Additional info:
Plant has been showing this symptom for the past two waterings, and it's only after watering that this happens. Naturally, you'd opt for overwatering here, but I weight my pots and I know when she needs a drink. My gut feeling is soil compaction, due to pouring water in from a measuring jug, perhaps too fast, but I thought the perlite would mitigate that issue. I get a good amount of runoff though, so I could be talking rubbish!

This issue seems more prominent on the newer growth.

--Pictures
This picture is taken around 9 hours after the watering.

Here is what she looked like after bouncing back after this first time it happened earlier this week... absolutely fine it seems minus some tacoing due to the heat. Very confused

 

[automan2]

I'll take a stab at it as I run BBLM and BB nutes under similar lights on 12/12...autos and photos
Some mods run BBLM so they'd chime in soon with help but my simple point of view is it
appears to be a ph problem primarily....
I always PH going in to 6.4 +- .... I've never checked what comes out.
After years with BBLM, that seems to be a happy point.
Make sure the environ is good temp wise and I'd bet she'll perk right up.

 

[Frank56]

I'll take a stab at it as I run BBLM and BB nutes under similar lights on 12/12...autos and photos
Some mods run BBLM so they'd chime in soon with help but my simple point of view is it
appears to be a ph problem primarily....
I always PH going in to 6.4 +- .... I've never checked what comes out.
After years with BBLM, that seems to be a happy point.
Make sure the environ is good temp wise and I'd bet she'll perk right up.

Thanks for the reply! I did wonder if it could be a PH issue, and the only reasons I thought it wouldn't be the case is that there is no discoloration of the leaves which led me to believe she was uptaking NPK just fine, combined with my already relatively neutral tap water, which I thought would be easy for BBLM to buffer to 6.5. Is this prolonged drooping a common sign of PH issue? I love learning about these plants, so would be good to understand what would cause this. Would the fact that she eventually perks back up go against this being a PH issue?

I have some BioBizz PH up/down ready to go, I guess I may have been a little naïve in thinking I wouldn't need to use it

 

[automan2]

Having been in the chemical business for most of my life, servicing nation wide manufacturing...we always tested water in each municipality to understand the vehicle carrying our products. Water changes significantly in just miles, much less states etc.
For any testing, I actually use DI water to isolate and identify possible culprits. Living in a large farming area, and being on a well, even then our ground water changes from season to season. Always at least ph .

 

[Frank56]

Having been in the chemical business for most of my life, servicing nation wide manufacturing...we always tested water in each municipality to understand the vehicle carrying our products. Water changes significantly in just miles, much less states etc.
For any testing, I actually use DI water to isolate and identify possible culprits. Living in a large farming area, and being on a well, even then our ground water changes from season to season. Always at least ph .

Oh I completely understand the importance of PH when growing, it's just that a good soil (BBLM should be fine) should buffer the medium to 6.5. I did mention that I don't PH my solution, but I do have some cheap test strips, just so I know it's not completely out of whack and sitting at 8, for example. I've seen experienced growers say that PHing solution is a must, and I've seen experienced growers say that they never bother PHing their solution when growing in soil; both had good yields in the end.

I've gone ahead and ordered a BlueLab PH pen based on your evident experience, so thank you for that (even if it's not a PH issue, you know far more than me, and it can't hurt to put things in at 6.4), but would be good to get a second opinion on this issue

 

[Proph]

When is the droop happening? Before lights out? I don't think this is a ph issue at all. You'd have multiple issues if the ph was off.

 

[Frank56]

When is the droop happening? Before lights out? I don't think this is a ph issue at all. You'd have multiple issues if the ph was off.

I thought so too, I thought I'd see more discoloration on the leaves.

So, I watered at 2am last night (odd time, I know.. lol), and woke up at 7am (baby duty!), the leaves were like they were in the picture. 3 hours later, still the same (this is when I took the picture).

When I took the picture, it was 2 hours before lights out (12pm is lights out), but they'd been like this for a while. Lights are due to come back on in about 15 mins, and I expect her to perk up (will update in couple of hours). Do you think it could be a combination of drooping before lights out, and the drooping you see after watering?

Cheers for the response!

Edit: Just had a check on her as lights came on, and some of the sites have leaves starting to raise up again in anticipation of the light, so it looks like she'll be looking good again in a few hours (will post pics later). Really lost as to why the drooping is so bad for so long though.

 

[Proph]

It's most likely Circadian rhythm. You should read up on it. Most plants start to rest a few hours before light out. It takes a lot of energy for the plant to keep all the leaves looking perky, so they start to rest and conserve energy a little early (usually 1-5 hrs before light out).

 

[Frank56]

It's most likely Circadian rhythm. You should read up on it. Most plants start to rest a few hours before light out. It takes a lot of energy for the plant to keep all the leaves looking perky, so they start to rest and conserve energy a little early (usually 1-5 hrs before light out).

Thanks for that, I'll be sure to educate myself. I knew they droop before lights off, and drooping after a good watering is also common, but I didn't know it could be up to 5 hours before lights off. I think that makes a lot of sense then, combined with the drooping from the watering. It's been 30 mins since lights on, and there's already significant improvement.

The last two 'problem' waterings have both been at 2am (I usually water earlier than this), so there is a definite correlation there. Thanks again for the pointers! Will post a definitive update in a few hours.

 

[Frank56]

Almost 3 hours since lights on now and she's picking back up, with top growth praying. Thanks for the help all, will try and water at lights on in future!