Mango Haze: Selection In Small Spaces

[cannatari]

Hiya, Resinbud. Thank you for the kind words, man. I enjoy your NH updates as well.


Well, the curse has been broken. 4/14 is way better than 0:

4 Mango Haze F2's ain't really enough to benchmark my male selection but if I get one female with no herm issues and doesn't smell like cat-piss then I will be very happy.

I'm so far, less satisfied with what 20 days of vegging in the cab has got me. It's still producing short, lettuce-like plants. Everything indicates that they are healthy with good appetites but they just won't stretch. I converted the bulb from MH to HPS a few days ago to see if the light spectrum is a factor. I've got 'em about 3 feet away from the lamp which will work out nicely if they like it because I won't have to raise and lower the hydro throughout the grow. I'm hesitant to initiate flowering until I see them look like the plant in the Growdrobe did when it was vegging...the very plant these plants came from.

They were in stasis and had no new root growth for the first week I had 'em in there so the pic is more like 2 weeks of growth. I topped 'em about a week ago as well. They're showing minor tip burn at 600ppm @ 5.7 pH.

Peace.

 

[wonkadonk]

weird? what's the water level? are they getting cold temps?

 

[cannatari]

Hiya, Wonkadonk. Yes, it's definitely weird that I can't get the same results with the same gear. It's hard to suspect that the hydro is to blame since the roots look perfect. The root tips dried up on the clones prior to the transplant is why I had the hiccup. The only factor left is the light. I had a MH in there for their transition but maybe they didn't like it. I'll know something in a couple of weeks.

Peace.

 

[cannatari]

Build 2.0 Update

So the pH has gone up to 5.8 and the ppm's down to 550 from 600 in 2 days which is a sign of good appetite and that I'm underfeeding so I'm going to conclude that these plants are in week 3 of veg as per the manufacturer's instructions (550 ppm for week 2 which is too weak right now) and start them on a diet of 750 ppm. Maybe my hiccup was only a couple of days. IDK, but I'm right on schedule nonetheless.

Peace.

 

[cannatari]

So...I put a radio in the grow cab a few days ago. My girl and I are on the road and I decide to tune in to the same station that the plants listen to and this is the song that came out, ironic as hell:



Peace.

 

[cannatari]

Hey Cannatari!
I read some of the posts a while back about the discussion of VPD and air pressure. The VPD measurement can be affected by barometric pressure because of all the reasons described in the article you cited.

Vapor pressure is the pressure of the gas phase that is in dynamic equilibrium with the liquid phase from which it evaporated, inside a closed system. Plants are not really closed systems so we adapt these measurements best we can to describe a certain natural phenomenon.

IMHO VPD is a misnomer. VPD is more of a measurement of the concentration gradient between the vapor pressure in the leaf and the vapor pressure in the ambient air.

It gives us an idea of how fast transpiration will occur. The larger the VPD the faster the plant will uptake (and deplete) it's water. Too high or too low of transpiration negatively effect photosynthesis.

Also, I think with hydroponics (specifically, aqua culture) this is much less of a problem because the roots are constantly bathed in water, therefore, transpirtation always has a supply of water to the leaf.

Negative pressure in the grow room must be bad once you reach a certain level, that could definitely mimic high altitude but in most circumstances I don't think mild negative pressure will really effect things...especially if your relative humidity is between 40-70%.

Since you have a small space you may well have exceeded the negative pressure threshold that may have caused issues. It will be interesting to see how the next round turns out.



Cheers,
Sensi

Hiya, Sensi.

I'm probably a rotation away from experimenting with VPD since the recent changes to the grow cab that I made are technically improvements toward proper Atmospheric Pressure. Once I do a run with a handle on that, I will investigate the need for me to maintain proper VPD. It kinda scares my to flower at 70% humidity like the VPD info recommends now that I have experienced mold issues for the first time but there is the chance that mold thrives on the water that is transpired by the plant and not water in the air. High humidity will cause the plant to transpire less moisture so it could be one of those situations where the solution is ass-backwards from what logic would have you believe. Example: if you fight humidity by exhausting more air, you're actually lowering the Atmospheric Pressure in the room and thus increasing transpiration which will probably make the problem worse. This is definitely going to be a challenging subject. Thank you for your thoughts on it.

Peace.

 

[cannatari]

Day 27

I had to update today because the plants have already consumed my add-back from 4 days ago. The EC was (current/previous) 600/750 ppm and the pH was 5.9/5.5 and about 4 gallons of water was missing. This is the hungriest Mango Haze I've seen yet. I bumped 'em up to 800 ppm.

I am also starting to see some branching and a reduction in "clawing" since I switched to HPS:

EDIT: On closer observation, the plants are not stretching as a whole, only the new growth has good branching. The old growth is still the same, as if the cells have "memory" and are well established.

Peace.

 

[cannatari]

Color Spectrum - Solved!

This is a huge subject that I have done much reading on. Here it is in layman's terms.

Photosynthesis occurs at all frequencies of visible light. Even green because all light has photons and it is photons that allow photosynthesis to take place. Because of the size of the plant's light receptor, it can absorb all of the photons at some wavelengths and very few at others:

You've seen the LED grow light manufacturer's charts that claim that because they only produce light in the nm that plants can see makes them twice as efficient. The chart says that at 650nm, an LED is producing light that peeks at 85% photo response. At 625nm, an HPS peeks at just 25% less. HPS produces way more photons than LED's so the matter of how much photosynthesis is actually taking place is probably the same for the amount of energy that is consumed by either one.

You can see that at 425nm, the plant is able to absorb all of the photons at that frequency but that still does not mean that it does:

The reason is because chlorophyll A is the primary component of photosynthesis and the plant has no use for extra chlorophyll B. Different ratios of chlorophyll A or B can affect growth but there will always be more A than B.

Plants convert the left-over photons from wavelengths out of the preferred frequency to heat energy that can damage tissue. So even though a plant can photosynthesize under green light, it repels so many photons that you would kill the plant with heat energy before you could provide for photosynthetic requirements.

IMO, the best grow bulb will have lots of red photons. Plants produce the proper ratio of chlorophyll A and B in the red spectrum and the difference in photon efficiency at that temperature range is only +/- 12.5%.

Where does this leave my color filter experiments? To block/cut all temperatures below 600nm. Maybe Haze will thrive at 100 watts/ft2 if I block harmful photons.

Experiment #2: Full flowering cycle at 600 nm and higher.

Peace.

 

[Cptn]

Hiya, Sensi.

I'm probably a rotation away from experimenting with VPD since the recent changes to the grow cab that I made are technically improvements toward proper Atmospheric Pressure. Once I do a run with a handle on that, I will investigate the need for me to maintain proper VPD. It kinda scares my to flower at 70% humidity like the VPD info recommends now that I have experienced mold issues for the first time but there is the chance that mold thrives on the water that is transpired by the plant and not water in the air. High humidity will cause the plant to transpire less moisture so it could be one of those situations where the solution is ass-backwards from what logic would have you believe. Example: if you fight humidity by exhausting more air, you're actually lowering the Atmospheric Pressure in the room and thus increasing transpiration which will probably make the problem worse. This is definitely going to be a challenging subject. Thank you for your thoughts on it.

Peace.

Great post Cannatari!
This completely jives with my understanding of VPD.
In my bunker, I recently opened a second 4" air intake and the exhaust fan seems to be moving with less strain and moving more air.
I still have negative pressure in the space, but it is MUCH less than before.
I have a second fan I was planning to add, but I think I might have what I need with a single now that the intake restrictions have been improved.
I have been having humidity issues too but the plants are thriving, so hopefully my ventilation changes will improve things.

Enjoying your grow. Great work!

Cptn

 

[cannatari]

Hiya, Cptn. If your ears don't pop when you enter your bunker, you're probably in good shape.

Thanks for the kind words.

Peace.

 

[cannatari]

I've been refining my filter selection and today I picked up the one that I will use throughout this next round of flowering. I took this split shot picture so y'all could get an accurate idea of how things look in there:

If the plants on the right don't look green, it's because there is no green light to reflect, right?

Here are the stats:

As with my Day 27 update, I will more than likely be using a blue filter for photographic purposes through the course of this grow so don't get confused when the pics look like normal light.

Peace.

 

[cannatari]

Update

Not allot to show for 5 weeks of vegging but I committed to withhold from flowering until I saw these girls looking proper. I'd say that things have definitely improved so in the 2 weeks that I might be behind, I was able to resolve some longstanding issues. My schedule is going to allow me to pay very close attention to them next month so I decided to wait till then to initiate flowering which will also reveal the effects of a couple more weeks of vegetative growth under the new circumstances.

I've never been more confident about my bullpen. This next round of flowering is going to be a new level of achievement for me. I'm stoked!

Peace.

 

[cannatari]

On second thought, they look amazing compared to last week. This photo is 7 days old:

Forgot to mention that the EC is down from 820 to 770 ppm, pH 5.7 from 5.5. No adjustments made.

EDIT: Also the part about loosing 4 gallons last week was wrong. Apparently it takes about a gallon to prime the system (-1) and I refilled it while it wasn't running (-2). I only lost 2 gallons that week, not 4. LOL!

Peace.

 

[cannatari]

My Perspective On The Light Distance Chart

Most of us go by this chart but it's not accurate in regards to photosynthesis. It, like everything else, is based on human visible light and not plant visible light.

I have experienced less diffusion with distance since I've been using the orange filter. The light that our eyes see diffuses faster than the light plants see. In short, a light intensity meter would not read as much loss with distance under the orange filter.

The chart would have you believe that your 600 watt HPS is loosing 2000 lumens with each inch of distance but that is a poor representation of the effective amount of photosynthesis taking place at those distances. I bet the real number is closer to 1%/inch loss not 10% like the chart shows from 20" to 21". It's ridiculous to think that your yield could suffer a 10% loss because your light was 1 link of chain too high. Get outta here!

Peace.

 

[cannatari]

That's my boy!
(not my hand)

Peace.

 

[cannatari]

48 Days Veg

I'm nailing these formulas as of lately. The hydro went 11 days maintenance free with the least amount of pH fluctuation I have ever achieved. My garden has never looked or smelled better.

I'm thinking it's time to flower!

In other news, the Mango Lights grow yielded 3.5 oz. Given the fact that was with a 150 HPS, it's like pulling 14 oz with a 600 HPS so we got pretty close to the mark over there. We left her in 12/12 to see if she will flower perpetually and new pistils have recently started to emerge!

Peace.

 

[Cptn]

Great update Cannatari.
Girls are definitely looking ready to flip.
What's the story behind those playing cards?

 

[cannatari]

Hiya, Cptn. The cards are from a game called "Weed". WEED CARD GAME, Party & Group Games, Risque Games at Games by James. It's actually allot of fun to play. I highly recommend picking up a deck if you ever come across a one.


Peace.

 

[cannatari]

Hiya, GM1.

Allow me to welcome you with a pic of my recent defoliation exercise:

Peace.

 

[cannatari]

Day 11 of Flowering

Everything is off to a great start!

I don't know what else to say, everything is just awesome!

Peace!