Army of Dankness - Bruce's Budtastical Battlepalooza

[Bruce Campbell]

In Bruce’s Blueberries, we showed that Bernstein’s 160 ppm-N optimum for photoperiods was a workable solution for the management of home cultivation programs for autoflowering cannabis.

In this grow series, we'll evaluate the use of a standard feed formula and fertigation plan against different genotypes and morphologies. We'll also investigate Zheng’s statistically derived optimum of 190 ppm-N and apply stricter controls to cation ratios. Each grow will be a 2-plant side-by-side comparison of selected strains grown in peat on a mineral salt-based fertigation plan.

Throughout the grow, I'll also update and share data forms and spreadsheets that I use to log and track each grow. I'll organize and share those through a "Table of Documents" on Google Drive that I will periodically update (link here). Major grow journal entries and other updates will be identified by threadmarks.

 

[Bruce Campbell]

A bit of background on our hero...
Some years ago, I was minding my own business, hanging out in housewares, when I heard that those hippies in government finally decided to legalize marijuana.
But, the all important question remained:

"Well, no," they told me. "But, you can grow your own!"

Soon, I found myself transported to a strange and distant land:

Where I discovered a tome of ancient and forbidden knowledge:

I broke out my old high school chemistry books, but years of prohibition had prevented these dark arts from being discussed openly. However, with evil rising once again across the land, this was finally beginning to come to an end. So, I did what I always did in school - I copied off the nerds!

I originally based my nutrient ratios on (at the time) more recent research by the Israeli Ministry of Health and University of British Columbia into optimal nutrient levels for photoperiod cannabis. I originally started with a random blueberry autoflower strain to see if those levels would create any issues for autoflowers.

Sure, I got a bit distracted growing an army of buds along the way (and, well, because of

), but now I'm back baby!

 

[Bruce Campbell]

So, the good stuff:

The magic formula I typically use is "any feed combination that provides the following nutrient levels"

I haven't scoured PubMed for any updated research since I started 3-yrs ago, so there may be better info published since then. If anyone else wants to take a look and let me know (hint hint)...

This grow I'll be targeting the upper end of the N range (190 ppm-N). I'll also be formulating around cation (K:Ca:Mg) ratios, including an N-reduction during bloom, and updating for MC's new Part A formulation. Overall, this means a 4-part feed formulation (plus a 5th pH adjuster if needed). Without including pH adjustment yet, feed plan for this grow would be:

 

[Bruce Campbell]

Seeds finally sprouted today. Took a day or so longer than I'm used to. I just plant in place and haven't had any issues yet - at least not enough to switch over to paper towel method. Not the best method, but below is what I do for each new bean:

Germination

Stage Definition

• Includes preparation and conditioning of grow containers and media
• Day -X = Days before Day 0
• Day 0 = First day of above-ground shoot (or day of transplanting)

Preparation

• Clean and prep grow area
• Fill bags with media
• Record dry weight of filled bags (and drip trays, etc)
• Irrigate bags with nursing solution
  • Grow Formula - 50-75% strength
  • Fill to saturation + run-off
• Drain / sit for 1-2 hrs. Measure saturated weights.
• Sit for 0-7 days

Planting

• Measure current wet weight
• Re-saturate with nursing solution as needed
• Form irrigation trough (~1-in deep) at mid-diameter
• Form slightly raised (~¼-in) mound at center
• Drill approximately 1-in deep
• Plant seed

Germination

• Use grow lights on standard timing and distance to warm soil
• Irrigate as needed
  • Pure RO/DI or 25%-50% nursing solution
  • Apply with pipette to avoid disturbing soil
  • Avoid applying directly on top of planted seed
  • Keep soil moist (to counteract evaporation) but not saturated
  • Approximately 10-30 mL daily
• Sprouting should occur in 2-4 days
• May need to remove seed shell if shell hangs on cotyledon

 

[Bruce Campbell]

Still pretty much just bags of dirt:

I started outlining some articles in the offsite Drive folder, and building out the grow report spreadsheet to include T/RH and fertigation log sheets. Even put together my first graph!

 

[Bruce Campbell]

Duke sprouted a bit stunted, but seems to be getting better. Not bad enough to restart. I suspect evaporation could be messing with pH, so next watering should probably be just RO to offset.

Would be nice if I could remove that from the water usage data - i.e., right now plots are showing 'evaporation + plant usage'. But, I've also been fiddling with room RH, lighting, etc. Evaporation will be less noticeable in the data as plant usage becomes bigger.

Otherwise, I switched lights to 100% and got room T/RH to the point where I'm comfortable removing domes.

Also, checked and compared leaf temps between plants a couple times - I've always wondered if / what 'non-VPD' conclusions you could deduce from that data.

 

[Bruce Campbell]

@Frankthetank @Mañ'O'Green @Lil Dab

What do you think about the cupping on RBF? Too much?

I haven't had a fan in there - just hot stagnant air? Otherwise, trying to decide feed as planned (50%) or just irrigate (RO)?

 

[Bruce Campbell]

R1 - RBF/Duke got 75% Veg to run-off, plan to do 100% Veg next feed. RBF still pulling ahead in leaf area / water usage. But, otherwise thriving.

Time to start tracking / logging heights more (plant & lights) before stretch starts.

M1 - Sawney's are off and running. Using 3-gal pots for these guys. They're on a '50% pre-charge / plant in place / then RO only' diet for now (+10 ppm orphan souls for deadite).

Project Update
FYI - I'll start using 'R' to refer to my 'main grow' rounds and 'M' to refer to my second 'mini-battle' grows.

E.g., BBB-R1-D22 and BBB-M1-D6, etc.

You've been warned.

 

[Bruce Campbell]

Duke vs. RBF
RBF is still bushier / thirstier, but Duke is getting taller / quicker.

I was expecting stretch to not start until now-ish (~Day 30), but they already put on a good bit of height last week.

Feed is 100% now, and lights are 20/4.

Deadite vs. Lecter
Feed - 25-33% (ramping up)
Lights - 100% @ 18/6

 

[Bruce Campbell]

Duke vs. RBF

Duke is already at +36" (soil to tip). I guess basketball tryouts are next.

I feel like in the past, when I've had some seedlings struggle like the Duke, they've gone on to be on the taller/faster/stretchier side. But, overall, probably just sativa vs indica differences between the two. Regardless, Duke is gonna need some supports or training soon.

The noise/ripple in the daily water graph is just sampling issues (i.e., calculating 24-hr daily usage from a 2-hr period vs. a 2-day period, including / not including lights off, etc). The total / averaged water use looks like maybe the air flow had some impact on evaporation. That's something that's probably better to look into during flower instead of stretch, though.

Deadite vs. Lecter

These two seem to be doing great for just being shoved in a closet. Should be starting stretch later this week.