Matching ppms to umols?

Southernontariogrower said:

My girl is running this cycle solo
Thug pug genetics
15gal cloth pot wrapped in poly leaving top and bottom with a few inches.
Wrapped when brought in, figured more room to root and conserve water and nutes
My light rated 1480 umols at hight of 1 ft, sphere tested 600w
Growing indoors then outdoors for 40 days
June 24th brought in and ran under leds 24x7
Half power or less at first then slowly increased
Flipped July 1st
First full strength feed made 5 gal bucket
Fed about 3g today
No runoff to speak of
Ppms were at 1550 approx.
pm is proliferating in my zone
Found a few spots today and removed fin.
But question is should nutes match light?View attachment 4960553
Guess my vpd is shot to shit
Temps been in 80s
Rh has been in 50s low 60s and is highest lve seen this grow but with all the water in there l understand
Rh *68 atm and temps lowest during lights on at 78.6f

My question again should light output match feed input?

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Tracker said:

At an ideal temp, pH, and RH, the amount of nutrient ppm's the plant can make use of depends on the photons and on the CO2.

6H2O + 6CO2 ----> add photons ----> C6H12O6 + 6O2

That is photosynthesis. To drive the photosynthesis more you need more CO2 and photons. The other nutrients you add make building blocks of new plant material, hormones, etc.... to support this activity.

At least that's what I learned after a bunch of Dr. Bruce Bugbee videos.

So the answer to the question is that there is a balance between light intensity, nutrient uptake, and CO2.

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NorthernHuntingMom said:

Bugbee is really good. A few of his comments about light rrally stick out.
Cannabis can handle a LOT of light, even as seedlings. The amount of light will govern the amount of every other vital component but it is important to remember that cannabis is as thirsty as it is light loving. It is easy to create an imbalance of nutrients with high light conditions. Cannabis drinks so much water that it is easy to over feed. I know that I will try to underfeed any time I notice a stressed plant.

How many here take a soil sample to their local county agriculture office for a soil analysis?

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Rocket Soul said:

When you add CO2 you need to add a bit more heat and your vpd may get a bit wacked up as far as transpiration: CO2 tend to close the stomata and decrease transpiration. This can be fixed by adjusting your vpd or by adding a little blue, preferably somewhere around 420-430nm.
You'll also need the extra heat for higher metabolism. Your plants, some have burnt tips so they don't look like they're using all the feed your giving.

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Rocket Soul said:

It's hard to say about CO2, at least from a theoretical standpoint. Is your grow sealed? Would you be able to measure how much CO2 rise over night? This would give some important info. Big rise and increasing from one day to another means the plant is working harder every day and you don't have too little CO2. But since it also closes the stomata the transpiration might be suffering, no drinking no growing. Don't go overboard on CO2, we had our veg super fucked slow and shitty by burning to much gas. If you plan on heavy duty CO2 then make sure you have good control over temps and rh independently from each other or even better some blue light on tap.

We couldn't compensate with environment or spectrum in our veg and the growth was shit.

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