Why would defoliation increase stretch rate
- Thread starter goskya
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MFB
Active Member
20 fan leaves from the one plant? That seems like it would cause a lot of stress. I keep all my fan leaves on for as long as I can, they pump lots of water up the main branch. From my little experience, the first 3 weeks is a lot of stretching. They still grow pretty steady afterward also. You may need a bigger grow area or to tie her down a little.
JohnnySocko
Active Member
ever seen pictures of starving POW's, refugees et et? ...same principle: the plant is starving (saying that w/o being smart alec)
I don't understand your analogy. And I'm doing rdwc, she always has access to food and water.
harris hawk
Well-Known Member
Plants strech the first 4 weeks of flower and defolation does increase your yields
CaretakerDad
Well-Known Member
Please do some reading on basic plant physiology before you start advocating this defoliation insanity. When you defoliate you remove the engines that drive plant growth........ period. There is much attention paid to light reaching all of the leaves which is only a part of the function of a leaf.
Please note the activity indicated by the red letters, CO2 in and O2 out. This capturing of carbon ONLY takes place in the leaves of your plant. Carbon is the building block for all complex carbohydrates required for growth, trace elements that complete the process are what you provide by fertilization. When you defoliate, the "growth spurt" you notice is your plant desperately trying to repair the damage you have done to the system it has crafted to collect energy and provide for eventual reproductive growth (buds). Please do not confuse defoliation with pruning which is often necessary especially with indoor crops to provide for proper ventilation to prevent mold.
In addition to this there are structures called guard cells that serve to regulate water retention/loss depending on the heat and humidity in the environment. Removing leaves inhibits the plants ability to respond to variations in heat and moisture levels.
Without proper respiration and transpiration any living thing suffers......basic biology folks, learn how to walk before you try to run or you will fall on your face. Good luck
Please note the activity indicated by the red letters, CO2 in and O2 out. This capturing of carbon ONLY takes place in the leaves of your plant. Carbon is the building block for all complex carbohydrates required for growth, trace elements that complete the process are what you provide by fertilization. When you defoliate, the "growth spurt" you notice is your plant desperately trying to repair the damage you have done to the system it has crafted to collect energy and provide for eventual reproductive growth (buds). Please do not confuse defoliation with pruning which is often necessary especially with indoor crops to provide for proper ventilation to prevent mold.
In addition to this there are structures called guard cells that serve to regulate water retention/loss depending on the heat and humidity in the environment. Removing leaves inhibits the plants ability to respond to variations in heat and moisture levels.
Without proper respiration and transpiration any living thing suffers......basic biology folks, learn how to walk before you try to run or you will fall on your face. Good luck
Well the first part is right..... BTW, plant foods high in phosphorus add to the stretch. http://www.gpnmag.com/what-really-causes-stretch
bwest
Well-Known Member
So, if you had 20 solar panels and took 10 away, you would generate more electricity?
AimAim
Well-Known Member
Fresh 2 De@th
Well-Known Member
Defoliation- Source vs. Sink:
First of all, you will need to understand the concept of Source vs. Sink within a plant. Pretty self explanatory, a source is any part of the plant that generates more photosynthate (sugar) than it requires for growth, and a sink is any part of the plant that requires more photosynthate than it can produce (or is producing). What is key to understand with this is that a plant tissue can change from sink, to source, and back to sink all as part of the plants natural process. For example, a newly forming leaf (fan leaf or bud leaf) is always going to be a sink, requiring more sugar to grow than it is currently producing from photosynthesis. . . but once that leaf has reached close to its mature size, it is producing much more sugar than it requires because it is hardly growing at that point. . . .and then again as that leaf becomes older and cells start to get older, the chlorophyll will actually lose effeciency and although the leaf may still look green and healthy, it is no longer generating more photosynthate than it requires to stay alive, and therefore older leaves become sinks again!
There are also parts of the plant which will almost always be sinks. Those are things like the roots (obviously no way of producing photosynthate, but still require it), the flowers on most plants because most flowers contain very little to no chlorophyll compared to a leaf, and seeds are always going to be sinks (the strongest sink).
The important reason I am explaining the Source vs. Sink relationship is because when you have too many sinks and not enough sources, your yield goes down and the overall vigor of your plant is reduced. So to maximize yield and sugar content in the final product (the buds), growers should try to eliminate other sinks as much as possible, while maintaining as many strong sources as they can without risking poor airflow or reduced efficiency with too much shading.
Keeping all this in mind, you can guess that a leaf which is receiving less light (heavily shaded) is most likely going to be functioning as a sink in the plant, drawing sugar away from other sinks that you may be more concerned about such as the buds. Removing leaves above the shaded leaf may give it more light, and maybe enough to start generating more sugar than it needs, but the lower down the leaf, the sooner it will be past its highest efficiency and the closer it is to becoming a sink permanently because of photosynthetic efficiency loss. Therefore, I tend to remove older fan leaves (less efficient) first before I go removing mature newer leaves higher up on the stems because they are more efficient.
Now, once you have removed any leaves that are past their prime, you may still have some fan leaves shading other bud sites, which in cannabis do produce their own smaller bud leaves. The larger fan leaves are MUCH more efficient at producing photosynthate than the smaller bud leaves, and because they tend to be more exposed to air flow they will also transpire more, meaning they help more water and nutrients move through the plant compared to bud leaves which have much less surface area and transpire/photosynthesize much less. So, that means it is better to keep large fan leaves, even if they are shading a bud site or two, because they will function as a source for the bud site (sink) and send its excess sugar to the bud. If you remove the fan leaf, the bud is already functioning as a sink, and so will have to get the rest of the sugar it needs from a different fan leaf on the plant (different source required), meaning a different sink is now getting less than it was because it is sharing its sugar supply from its own fan leaf. . . . this kind of sharing and relocating of sugar pathways takes extra energy in itself, and is not beneficial even if the bud site is no longer being shaded and can produce slightly more sugar on its own from the small bud leaves.
In conclusion, remove old fan leaves especially if they are no longer receiving any direct light. Try to maintain as many sources on the plant as possible by getting as much light and air flow to the newer mature fan leaves as possible. Remove any very low sinks that are far away from any strong sources because they will generate almost no photosynthate on their own, along with drawing photosynthate away from other sinks that are more local to the source leaves higher on the plant. And don't worry if your bud leaves are shaded, because they are sinks anyways, so the plant is pumping all the excess sugar from local fan leaves to the nearest/strongest sinks it can find (your buds)!!
First of all, you will need to understand the concept of Source vs. Sink within a plant. Pretty self explanatory, a source is any part of the plant that generates more photosynthate (sugar) than it requires for growth, and a sink is any part of the plant that requires more photosynthate than it can produce (or is producing). What is key to understand with this is that a plant tissue can change from sink, to source, and back to sink all as part of the plants natural process. For example, a newly forming leaf (fan leaf or bud leaf) is always going to be a sink, requiring more sugar to grow than it is currently producing from photosynthesis. . . but once that leaf has reached close to its mature size, it is producing much more sugar than it requires because it is hardly growing at that point. . . .and then again as that leaf becomes older and cells start to get older, the chlorophyll will actually lose effeciency and although the leaf may still look green and healthy, it is no longer generating more photosynthate than it requires to stay alive, and therefore older leaves become sinks again!
There are also parts of the plant which will almost always be sinks. Those are things like the roots (obviously no way of producing photosynthate, but still require it), the flowers on most plants because most flowers contain very little to no chlorophyll compared to a leaf, and seeds are always going to be sinks (the strongest sink).
The important reason I am explaining the Source vs. Sink relationship is because when you have too many sinks and not enough sources, your yield goes down and the overall vigor of your plant is reduced. So to maximize yield and sugar content in the final product (the buds), growers should try to eliminate other sinks as much as possible, while maintaining as many strong sources as they can without risking poor airflow or reduced efficiency with too much shading.
Keeping all this in mind, you can guess that a leaf which is receiving less light (heavily shaded) is most likely going to be functioning as a sink in the plant, drawing sugar away from other sinks that you may be more concerned about such as the buds. Removing leaves above the shaded leaf may give it more light, and maybe enough to start generating more sugar than it needs, but the lower down the leaf, the sooner it will be past its highest efficiency and the closer it is to becoming a sink permanently because of photosynthetic efficiency loss. Therefore, I tend to remove older fan leaves (less efficient) first before I go removing mature newer leaves higher up on the stems because they are more efficient.
Now, once you have removed any leaves that are past their prime, you may still have some fan leaves shading other bud sites, which in cannabis do produce their own smaller bud leaves. The larger fan leaves are MUCH more efficient at producing photosynthate than the smaller bud leaves, and because they tend to be more exposed to air flow they will also transpire more, meaning they help more water and nutrients move through the plant compared to bud leaves which have much less surface area and transpire/photosynthesize much less. So, that means it is better to keep large fan leaves, even if they are shading a bud site or two, because they will function as a source for the bud site (sink) and send its excess sugar to the bud. If you remove the fan leaf, the bud is already functioning as a sink, and so will have to get the rest of the sugar it needs from a different fan leaf on the plant (different source required), meaning a different sink is now getting less than it was because it is sharing its sugar supply from its own fan leaf. . . . this kind of sharing and relocating of sugar pathways takes extra energy in itself, and is not beneficial even if the bud site is no longer being shaded and can produce slightly more sugar on its own from the small bud leaves.
In conclusion, remove old fan leaves especially if they are no longer receiving any direct light. Try to maintain as many sources on the plant as possible by getting as much light and air flow to the newer mature fan leaves as possible. Remove any very low sinks that are far away from any strong sources because they will generate almost no photosynthate on their own, along with drawing photosynthate away from other sinks that are more local to the source leaves higher on the plant. And don't worry if your bud leaves are shaded, because they are sinks anyways, so the plant is pumping all the excess sugar from local fan leaves to the nearest/strongest sinks it can find (your buds)!!
Fresh 2 De@th
Well-Known Member
http://link.springer.com/article/10.1007/s11099-012-0029-3
Abstract
Leaf canopy plays a determining role influencing source-sink relations as any change in source activity (photosynthesis) affects sink metabolism. Defoliation (removal of leaves) influences growth and photosynthetic capacity of plants, remobilizes carbon and nitrogen reserves and accelerates sink metabolism, leading to improved source-sink relations.
The response of plants to defoliation could be used to manipulate source-sink relations by removing lower and senescing leaves to obtain greatest photosynthetic capacity and efficient carbon and nitrogen metabolism under optimal and stressful environments. The present work enhances our current understanding on the physiological responses of plants to defoliation and elaborates how defoliation influences growth, photosynthetic capacity and source-sink relations under optimal and changing environmental conditions.
Abstract
Leaf canopy plays a determining role influencing source-sink relations as any change in source activity (photosynthesis) affects sink metabolism. Defoliation (removal of leaves) influences growth and photosynthetic capacity of plants, remobilizes carbon and nitrogen reserves and accelerates sink metabolism, leading to improved source-sink relations.
The response of plants to defoliation could be used to manipulate source-sink relations by removing lower and senescing leaves to obtain greatest photosynthetic capacity and efficient carbon and nitrogen metabolism under optimal and stressful environments. The present work enhances our current understanding on the physiological responses of plants to defoliation and elaborates how defoliation influences growth, photosynthetic capacity and source-sink relations under optimal and changing environmental conditions.
Fresh 2 De@th
Well-Known Member
same goes to you.
dannyboy602
Well-Known Member
interesting read. i'll have to read more about the topic. thanks for the references.
Fresh 2 De@th
Well-Known Member
hmm, it seems, like most, you just repeat what you hear and have no knowledge on the topic as well.
you compare leaves to solar panels but at the same time fail to take note that a solar panel setup isn't build the same as the way a plant grows. i wonder why? oh, that's it, it would be counterproductive to stack solar panels the way a plant grows. so what was your point again?
to the op, stretch is in the genetics. the only way to inhibit stretch during bloom is to top a wk or two before inducing 12/12, lst'ing or pinching the main stems.
PetFlora
Well-Known Member
I'll let the pics speak, I remove the first set of fan leaves below the 3rd top nodes on each branch, BUT, my hydro top feed method feeds 32 seconds every 18 minutes while lights are on, offsetting primary leaf storage. I actually increased feed from 27 seconds to see whether I would get some tip burn, but no. I also increased ppm from ~ 1200 to ~ 1500, still no tip burn. I can do this because my medium is fast draining but holds enough moisture between so roots do not dry, all of which means Primary Shade leafs are not needed
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Please do some reading on basic plant physiology before you start advocating this defoliation insanity. When you defoliate you remove the engines that drive plant growth........ period. There is much attention paid to light reaching all of the leaves which is only a part of the function of a leaf.
Please note the activity indicated by the red letters, CO2 in and O2 out. This capturing of carbon ONLY takes place in the leaves of your plant. Carbon is the building block for all complex carbohydrates required for growth, trace elements that complete the process are what you provide by fertilization. When you defoliate, the "growth spurt" you notice is your plant desperately trying to repair the damage you have done to the system it has crafted to collect energy and provide for eventual reproductive growth (buds). Please do not confuse defoliation with pruning which is often necessary especially with indoor crops to provide for proper ventilation to prevent mold.
In addition to this there are structures called guard cells that serve to regulate water retention/loss depending on the heat and humidity in the environment. Removing leaves inhibits the plants ability to respond to variations in heat and moisture levels.
Without proper respiration and transpiration any living thing suffers......basic biology folks, learn how to walk before you try to run or you will fall on your face. Good luck
harris hawk
Well-Known Member
So what you are saying that if one defolaited to much this will cause a smaller plant? Do not practice defolation/pruning but just remove the necessary leaves to let the "sun shine" usually fan leaves, but then again they are the leaves that catch the light necssary for good growth. Thanks for the information an picture a great help
fssalaska
Well-Known Member
Please do some reading on basic plant physiology before you start advocating this defoliation insanity. When you defoliate you remove the engines that drive plant growth........ period. There is much attention paid to light reaching all of the leaves which is only a part of the function of a leaf.
Please note the activity indicated by the red letters, CO2 in and O2 out. This capturing of carbon ONLY takes place in the leaves of your plant. Carbon is the building block for all complex carbohydrates required for growth, trace elements that complete the process are what you provide by fertilization. When you defoliate, the "growth spurt" you notice is your plant desperately trying to repair the damage you have done to the system it has crafted to collect energy and provide for eventual reproductive growth (buds). Please do not confuse defoliation with pruning which is often necessary especially with indoor crops to provide for proper ventilation to prevent mold.
In addition to this there are structures called guard cells that serve to regulate water retention/loss depending on the heat and humidity in the environment. Removing leaves inhibits the plants ability to respond to variations in heat and moisture levels.
Without proper respiration and transpiration any living thing suffers......basic biology folks, learn how to walk before you try to run or you will fall on your face. Good luck
Thats a pretty photo ! I take some water leafs off in late flowering and I have never seen anything but good as a results. bigger lower buds and have never seen stretch from defoliation in later 4th week plus flowering.
I think a lot of people here read much more than they try/do. Please always take the shit people say here with a gain of salt. theres lots of good growers here but there's also a hell of a lot of google experts without much real experience that love to spam post like they know something. good luck
PetFlora
Well-Known Member
Not sure this is addressed to me, but I keep top 3 node fan leafs until such time that the secondary leafs are developed. IMHO, 3 secondary leafs will out perform one old but similarly as much structure big fan leaf. Speedsters v old guy
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