Dialing In MEGA CROP for Auto's

[GeorgeCloney]

It's called the Calvin Cycle it's what plants do at night it's not photosynthesis

Ah thank you for the exact definition.
Both of you explanations make more sense than photosynthesis in the dark.
I need to research this Calvin cycle
And so if we can influence the plant to grow by night as much as by day, we just doubled our efficiency.
What I want and what the plant wants are two different things at times.

 

[4d-Rock]

So in attempt to dial in my v2 MegaCrop I’ve been working on an experiment with 3 Fantasmo Express from Mephisto Genetics.

All had a weak pre-charge to start in 2gallon pots filled with Pro-mix HP, weekly Foliar feeds with weak kelp solution and only plain water the first week
Starting week 2:
Far right has been getting fed every watering with 0.5g/gal SC and 1g/gal MC.
Left has only had ph water
Middle is following the recommended guidelines and had feeds with 0.4g/gal kelp, 0.5g/gal SC, and 2g/gal MC and upped to 4g/gal in week 3. But has plain ph water in between feeds.

All were topped at day 17

Here they are at day 29

This is what confuses me and makes me second guess how to read the plants.
The water only plant on the left looks great, only the cotyledons have just yellowed. But overall good growth and colour, and weirdly some minor clawing on some leaves that look like N toxicity (maybe a pheno trait?) but some straighten out.
The MegaCrop recommended guidelines in the center has the best growth, but not much more compared to the water only, similar N toxicity clawing on a few leaves, and just recently after the 4g/gal feed is showing some signs of minor tip burn.
The low consistent feed one was about 2 days behind when they popped initially and has been slower overall. A different structure with less side branch growth and were quite rigid. It also has very deep green fan leaves too.

Its still early days in this experiment, and I think stuff may hit the fan once flowering starts. But I have a plan and will keep to it. Will I have any answers by the end? Probably not, but interesting nonetheless. I think the differences will end up being more the result of phenotypes and individuality of the plants rather than nutrient regiment, but I may be surprised too.

Feel free to speculate and tell me what I’m doing wrong haha

 

[GeorgeCloney]

Yup, I completely agree about your pheno vs nutrients theory.
The plants below were babied with TLC.
In undersized airpots, falling over 10x a day in the wind and watered with a garden hose and city water
I gave up the MC to save $on these plant as they are photos (freebie seeds).
They have suffered water deprivation.
110 degree heat in the mid day sun.
And wind every day.
I cannot kill these F*ckers, and I'm trying hard.
If these were autos, they'd have been dead a long time ago

 

[4d-Rock]

Wow @GeorgeCloney , those are some pretty nice looking plants for being rejected haha

Well I've had a weird development in the experiment. They are in stretch now and are still looking pretty good, maybe a bit longer internodal length than one would like, but hey as long as they're happy.

So for the most part I haven't been watering to 10-20% runoff. Starting week 3 I was giving 1.5L/pot which gave a couple trickles of runoff, depending how dry they were. Previous to that I was giving 500ml-1L as the grew. Well yesterday at Day 32 I decided to up it to 2L/pot to get some runoff, maybe compare to see what is getting left in the soils with the different feed strengths..and I'm confused and surprised at what I found. And maybe it has to do with me doing it incorrectly, but I let it drip for 15-30 seconds and then started collecting runoff, maybe 20-50ml and then tested.

MegaCrop Recommended guidelines: Input 670ppm/6.1pH Runoff: ~1500ppm/5.8pH
Water only (had one weak feeding a week ago at like 270ppm): Input 55ppm/6.1pH Runoff: ~1000ppm/5.7pH
Low consistent feed: Input 270ppm/5.9pH Runoff: 1300ppm/5.9pH

I'm very confused now. The water only pot had a 0.5g/gal Sweet Candy/Megacrop charge at the very beginning, and only one feeding it's entire life....how in hell does it have a runoff of 1000ppm? And even the low dose is pretty crazy considering that I've never fed it more than 300ppm once. I'm less surprised at the Megacrop full dose but still that's pretty high.

Any ideas out there? Pro-mix HP is supposed to be fairly inert, so I don't think it's soil nutrients

The only thing I can sort of think of is that there is build up because I haven't been watering to enough runoff but that doesn't explain the high ppm of the 'water only' plant. Or the salt residue on the outside of the fabric pots are skewing the results as the the water passes through them. Or maybe pots have residual salts from previous grows, but before using again I scrub them down, soak them in water and rinse. And I did that like 3 times each.

However, the plants are still looking pretty good. Preflowering is starting to set in as stretch is finishing off. I'm going to keep up 2L feeds and monitor runoff to see if there is any change but I'll keep to the plan and see how things progress.

 

[GeorgeCloney]

@4d-Rock
Those are excellent looking plants!
I grow in SunShine4, ProMix and Coco.

For indoor grows I prefer the coco ( dries quick in a tent, so you feed more often),...wife hates that when I'm away on business

Promix and SunShine4 are pretty good mediums if you're growing outside.
I see you're growing in a tent.
Runoff is easier when growing outside (obviously).
In the tent can be a hassle, no doubt.

What kind of water are you using?
If city water, it could simply be the minerals and chlorine build up in the soil.
Having said that, the plants look great ( which is screwy??), but they're happy right.
Thats all that counts.

I've been following @pop22 and @Dabber advice on keeping my MC feeds under 500ppm.
I do however feed to runoff every time (outdoors / in 7.5L pots (2 gallon hercules airpots).
They are the plastic pots with slits in them.
I think they're great cause they work very well and are easy to clean at the end of the grow.

Nice grow you got going on, Cheers bro.
GC

 

[4d-Rock]

Thanks @GeorgeCloney , it has taken some time but I think I generally have the veg part down. Always room for some fine tuning though.

Our water comes from the lake, then goes through a charcoal and UV filter. It ends up like 60ppm and ~7ph. From everything I’ve seen, that’s reasonable water but the lake is quite murky so if there’s something in it that isn't being used I suppose it could build up in the medium.

Watering to runoff isn’t usually too big of a deal, my plants are usually small enough to pull out of the tent and put on a bucket. Toward the end of the flowering they can be a bit of a hassle.

For me it’s usually from here during the transition and flowering that have given me issues. Most of the reason for this experiment, tryOmg to pinpoint where the imbalance is.

The next feed of 2L has brought down the ppms of runoff a bit, but still rather high (850-1300). The water and feed as required plant is noticeably more lime-green then the other two so I gave it a second feed with 2g/gal.
The other two kept to their schedule and will be starting to introduce week flowering nutes this week.

 

[pop22]

I've been feeding this girl 550 ppms ( average ) since it was a week old. I'm in soil. I shoot for a PH of 6.45. I never water t runoff and I never bother testing runoff PH. Most of the 18 gallons of soil is recycled soil that's been fed MC 2.0. I've never had a problem with salts buildup. I have autopots with the same soil in them for close to three years that have been fed MC all that tine.

The Trainwreck clone in the background is a fussy bitch...... She doesn't like even slight variations in PH, she's fed the same MC solution as all my other plants. Could be the small pot too lol, I have another Trainwreck clone in a 2 gallon that's just fine.. go figure lol!

 

[GeorgeCloney]

I got my first tent last fall. A 2x4x5
Had 8 dwarf plants in it which was pretty much the limit.
Pre covid, I picked up a tray to put inside the tent. Friggin expensive for a plastic tray thats 2x4x6high.
But now I water to slight run off.
When I set up the tent this fall.
I plan on sitting the tent 6 to 10 inches off the ground with the tray inside.
This way, I can install a drain plug/valve and run off to a small bucket outside of the tent.

 

[pop22]

I have trays in my 2.75x2.75" and my 4x4 tents. I'm going to put one in my other 4x4. Instead of using it to catch runoff, why not bottom feed? I had 12, 2 gallon pots in the 4x4. I'd pour in 5 gallons and they'd absorb it in 2-3 days. Just like a big auto pot! My friend Tony21 grows monsters that way. He inspired me to go to trays.
I'll have to dig through my old pics, but I have oe of him with a plant in that tent that was way over his head! here's a pic of part of his 10x10x9 tent

I got my first tent last fall. A 2x4x5
Had 8 dwarf plants in it which was pretty much the limit.
Pre covid, I picked up a tray to put inside the tent. Friggin expensive for a plastic tray thats 2x4x6high.
But now I water to slight run off.
When I set up the tent this fall.
I plan on sitting the tent 6 to 10 inches off the ground with the tray inside.
This way, I can install a drain plug/valve and run off to a small bucket outside of the tent.

 

[GeorgeCloney]

I never even considered that
Thanks @pop22
I need to do some research on that approach.
Sounds like a solution for my wife feeding my tent when I'm away too
I can certainly see the merits in this using coco in a tent.