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Light to leaves--not necessarily to buds???

alltatup

alltatup

New member
I've been watching my current grow and this time I observed how the leaves stretch out on the plants during the first few weeks of flowering: lower on the plants, they stretch out where they are trying to get into the light. Thus, lower on the plant, there are leaves sticking out into spaces where the light falls, while the bud may be in shade.

So it's got me wondering about the whole "fattest buds in the light" debate: Is bud development based on the leaves surrounding that bud reaching the light as opposed to the bud reaching the light?
 
I talk about the behavior of photomorphogenesis with cannabis in my article on defoliation. Flowers do not exhibit any real level of photosynthesis or photomorphology. So leaves are infact the only sources of energy. This is why we can use narrow band or band limited wavelengths during flowering, such as high pressure sodium with excellent results, as there is no real effect of photomorphogenesis taking place. It is simply, pure photosynthetic production. There are aspects such as aroma and THC production which can be affected by specific wavelengths of light, however this is not a product of plant morphology to light but simple byproducts of genetic responses to ionizing radiation.
 
What he said about potomorphology.

I have tried both ways. Defoliating and not defoliating. I'm pretty sure my biggest yields came from non defoliated plants. However last grow I had one to bushy and big and it got bud rot. Apparently no matter how many fans I added the center of the plant stayed to "wet." So in the future I'll defoliate plants that large just for airflow.
 
Leaves are the sugar factories - don't need any $25 words - but I'm with Redwasp. Inside a tent with more than one plant you have to defoliate for air circulation - or - bud rot is inevitable.
 
So let’s define a few things here first: Fan leaves (the large leaves that stretch out from a stem and have no contact with the flowers) and Sugar leaves (the smaller leaves that touch the flowers and are usually frosted with trics). Both are capable of manufacturing food for the plant, so why are the larger ones needed? My theories are this: in nature the environment fluctuates; drought spells, cloudy days, too much or not enough wind, and nutrient availability will fluctuate with the biological influence in the soil. Nothing in nature is as consistent as the indoor garden is. So fan leaves are also storage cells for when times get hard for the plant. When the plant can not manufacture food on its own. (let’s use the example of a cloudy day) The fan leaves can provide enough stored nutrition to make it through the tough times. In the case of the indoor garden, these fan leaves are only nesessary if the grower messes up somehow. If the grower is able to maintain perfect growing conditions, the stored fan leaf energy is not required and the fan leaves are just blocking out light and wind to the lower portion of the plant in this case (plus those leaves are using up vital nutrients to remain alive). The plant realizes this, therefore puts more energy into developing the tops where the most light and wind hit. In the case of less fan leaves, the other parts of the plant are able to utilize all of the available nutrients contained in the soil.
Removing lower fan leaves exposes light and wind to the lower portions of the plant, and less leaves means more available nutrients (per kappa). The only trade off, is if the environment fluctuates and the plant needs those fan leaves stored energy... yields can suffer. On a flawless grow environment with little to no stress factors, a few fan leaves at the top of the plant and all the sugar leaves through out are able to provide enough energy to produce massive yields.
 
Redwasp I believe in a little defoliation for two reasons:
to open up space for more air flow, and
for allowing other parts of the plant to have access to light.

I think (I pray) I did my best defol so far, because they're covered with leaves and yet many bud sites (and leaves) are exposed to light. That's what I wanted: the light reach the inner depths.
 
Yes alltatup I do uncover bud sites, and when needed I also remove leaves to get better airflow. I usually also remove any of the stems that will end up being popcorn buds. I consider this pruning though because I do not remove any leaves that I dont have to.

I saw the pictures you posted of your defoliation and they look perfect. You did a GREAT job. And I'm no expert but I do not think the argument over defoliating vs not defoliating will ever end. I dont have a side on that argument. I do not know enough to know what works better for others. I only know what I find works for me.
 
Yea I believe plants make more foliage than they require, to feed the deer and elk. Gotta expect some grazing in nature and a hailstorm too. Perhaps some 60mph winds that rip some leaves off too.

Keeping all the leaves on, the plant seems to shed quite a few as the buds start to develop, like a sort of natural defoliation. I doubt any plant in nature is getting spoon fed nutrients and extra iron to keep things green, unless perfectly positioned over a carcass on a river delta. Underfed or more simple grows tend to see a strong fade with yellowing and senescence throughout bud development. Lots of leaves fall off before the buds are ready.

What I observed last defoliation: made for a better growers attitude when I can actually SEE more bud sites per eyeful. Happier growers spend more love for their plants. So it benefits my plants because it makes me smile to be able to see at once all those bud sites!
 
KingKush I get that same peaceful happy feeling training my plants. Of course I love the unknown of planting the seeds and am like a kid on Christmas when I plant new strains.

I choose to just prune specific leaves to make sure the plant gets airflow and that all the buds get light. I assume some might call what I do defoliating but I remove alot less than most people who defoliate.
 
Toker1 said:
So let’s define a few things here first: Fan leaves (the large leaves that stretch out from a stem and have no contact with the flowers) and Sugar leaves (the smaller leaves that touch the flowers and are usually frosted with trics). Both are capable of manufacturing food for the plant, so why are the larger ones needed? My theories are this: in nature the environment fluctuates; drought spells, cloudy days, too much or not enough wind, and nutrient availability will fluctuate with the biological influence in the soil. Nothing in nature is as consistent as the indoor garden is. So fan leaves are also storage cells for when times get hard for the plant. When the plant can not manufacture food on its own. (let’s use the example of a cloudy day) The fan leaves can provide enough stored nutrition to make it through the tough times. In the case of the indoor garden, these fan leaves are only nesessary if the grower messes up somehow. If the grower is able to maintain perfect growing conditions, the stored fan leaf energy is not required and the fan leaves are just blocking out light and wind to the lower portion of the plant in this case (plus those leaves are using up vital nutrients to remain alive). The plant realizes this, therefore puts more energy into developing the tops where the most light and wind hit. In the case of less fan leaves, the other parts of the plant are able to utilize all of the available nutrients contained in the soil.
Removing lower fan leaves exposes light and wind to the lower portions of the plant, and less leaves means more available nutrients (per kappa). The only trade off, is if the environment fluctuates and the plant needs those fan leaves stored energy... yields can suffer. On a flawless grow environment with little to no stress factors, a few fan leaves at the top of the plant and all the sugar leaves through out are able to provide enough energy to produce massive yields.
Click to expand...


I like hearing peoples theories, it allows you to think in ways you may not have before. Leaves in cannabis store very little starch. They produce photosynthates, and imediately shuttle this energy out through the phloem for use by the rest of the plant. Leaves, once matured are sources and stay as sources for the remainder of their life until senescence. Plants only require enough light that satisfies whats called the compensation point. For many plants this is usually around 60-90umols or 5000-7000 lux. This is an insanely low level of light which is always provided under any outdoor environmental condition. Which means they never have to rely on any stored resources for simply staying alive. But many perianual plants such as those with tubers, take advantage of stored resources for occasions such as this to continue growth. Especially during the winters or when major plant injuries occur. Cannabis however does not, cannabis and most other annual plants only store enough energy to contunue their respiration during times when there is no light (night time or dark cycle). They do this so well infact that they actually apply arithmetic calculation to make sure that almost all stored resources, manufactured during the day, is almost completely used before sunrise or the light cycle. Which is why whole plant regeneration is not possible with cannabis.

On another note, many studies on plant defoliation, shows that plants can tolerate up to 20% of loss of leaves. Which is assumed to be a compensation technique in anticipation of natural events where leaves may be lossed. Such as animals, weather, diseases etc.

I completely support the use of defoliation for improving the overall health of the plant, such as disease prevention, humidity, airflow etc.
 
Hmmm. I have read a few articles that say fan leaves store energy. Do you have anything that backs up that they don’t?
The leaves do store chlorophyll, otherwise they would not be green. I guess I am not following that logic. Here are 2 articles. The first is not very direct about this. The last article says this in the “against” section. It even references GWE in their research section. They are very direct about leaves storing energy for later.
https://www.google.com/amp/s/www.th...ert-light-into-energy-c8Rr2lIG2kWp_Fj7g7Ukuw/
https://www.santyerbasi.com/en/blog/cannabis-defoliation/
 
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Redwasp That's what this whole learning process is about for me. I've come to understand defoliation much better than I did before; there are certainly various reasons to defol or not to, dependent on environmental conditions.
 
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DrPhoton This is about photosynthesis, not photomorphogenesis. Photomorphogenesis has to do with how different light spectrums affect veg phase versus flower phase, but the issue I raise is different:

If photosynthesis can take place in leaves in various places on the plant where light wouldn't reach unless we train the plant, then lower buds will develop better because the leaves exposed to light are feeding them better than leaves in shadow.

So my issue is not about what kind of light we're using, but how we expose leaves to light during indoor flowering.

Now onto a second issue:

I've seen on this grow something that didn't happen so much before because I wasn't defoliating the right way: What defoliation allowed in veg and in flower was for more bud sites to shoot up and fill in the canopy. They shot straight up towards the light all over three out of four plants (Afghan Kush has been the lagger all along, and smaller than the other three, though she looks good for her size). It's like they were rushing to fill in the space in the upper canopy before someone else got there first.

So instead of trying to keep all the focus on the main colas, I left all these "survival of the fittest" type smart buds who made it up to the top. They were wonderful to watch in their insistence on gettin up there with the big dogs. Watching them climb and stretch out their smaller leaves is what got me wondering about this topic.
 
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Toker1 I liked the first article by Bergman, who says, quote:

"At night other necessary processes take place, such as the production of proteins. The energy needed for this involves the same chemical reaction, but then from right to left. The sugar stored energy and oxygen is converted into water vapor and CO2. This is known as dissimilation, or the breathing of the plant. The plant uses this energy to make other proteins which are not formed with the assimilation during the day. For this reason a marijuana plant requires a day and a night period."

Sugars formed during the day, and proteins formed at night.
https://www.themcaa.net/cannabis-proteins-amino-acids--immunity.html
 
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