When the plant is left to grow as it chooses, it usually has more branches than it has the energy to support. This means that a lot of energy is wasted on smaller branches, especially the lower ones. The energy need is so spread out that in extreme cases flowering takes a very long time as the plant tries to supply energy evenly to every location. By removing some of the less important and weaker branches, you can ensure that the larger branches produce a greater amount of high quality bud. The bud on the lower branches that receive less light usually end up as single “pop corn” buds that never truly mature, so it is best to remove them at an early stage.
You become the investment planner for you plants. Observe the growth and remove any branch that has long internodes (the space between the nodes) and any branch that stays significantly lower than the main shoots. These branches will get very little light and they will also have a hard time finding their way up to the well lit area. Most of the time I end up removing almost all the growth underneath the Scrog net, I only leave the fan leafs intact until the plant drops them by itself after the energy has been recovered. Pruning the lower limbs creates more air-flow under the plants
When it comes to removing leaf material opinions vary, some remove leafs and others, like myself, chose not to. I have tried both methods and can honestly say that there is no positive effect really from removing leafs. Keep in mind that fan leafs are the primary location for photosynthesis and that the plant also stores surplus energy in them. By removing the leafs you do double harm, you handicap the plants ability to produce vital energy and you also remove the energy that has already been stored for future use. Furthermore, although it cannot be observed with the naked eye, light actually passes through the leafs and that is why some of the lower growth stay green throughout the entire grow. It is better to tuck or tie the leafs under the canopy so that light reaches more bud sites, or alternatively cut the leafs in half.
Another thing to keep in mind is that there is a hormonal response in plants to being wounded. This includes a growth inhibitor called jasmonic acid. It tells the plant to favor defense over growth. The more you remove at any given time, the greater the response. It is therefore wise to trim the plants gradually althrough flowering, instead of removing all the growth at once. This hormone also plays a part in regulating the formation of trichomes, and that is probably why a little bit of stress is thought to increase potency. There is however a difference between stress and torture, a healthy plant will always produce more bud than a plant that has been severely handicapped.
Since most of the photosynthetic activity takes place in the fan leafs, the buds themselves do not need light, in other words, bud sites are activated by light when it hits the node but the energy is produced and transported to the buds from the leafs. This is where a Scrog net comes in handy, you can tie down the leafs without removing them and thereby allow more light to reach the buds while no energy is lost.
Sometimes you do not have a choice and must remove some of the growth in order to ensure that you get a good harvest. It all depends, some plants respond well to rigorous pruning but in general I would advice that you keep it to a minimum since there are optional methods to removing the leafs altogether. The rules of pruning are a bit different when it comes to SOG grows as you might have to remove some of the fan leafs because the plants are packed so close together.
I think that the best advice is to watch your plants closely and adapt your technique and grow style according to the needs of the plant
Nothing is set in stone when it comes to growing.
All grow rooms are different and so is each strain of cannabis. In fact every plant is different from the next so you will have to try out what works best for you and your plants.
Marijuana Pruning Tips
* Each time a growing tip is clipped, the stem branches into two shoots, which begin to grow from the nearest leaf axils.
* Pruning a growing marijuana plant is an easy way of controlling uneven growth without seriously harming the plant.
* Don't prune the growing tip of a young seedling until after the first five-bladed leaves have formed, and the vegetative stage has begun.
* Many growers prune the growing tips after four to five weeks growth to develop lower branches which will quickly fill all the horizontal space.
* The greatest potency of the growing plant is found in the growing tips, and by three months, they should make a high quality smoke.
* You can basically prune growing tips at any stage of the plant's development, but just don't overdo it.
* Severe pruning can harm the growth of the plant.
* It is always better to plan a pruning strategy for your developing plants, rather than haphazardly clipping off growing tips on an irregular basis.
* Each time a growing tip is removed, the plant takes a few days to recover before new growth resumes on that branch.
* The amount of new growth formed with continued pruning is limited by the genetic structure of the seed, and the conditions of the environment.
* It is better to prune your plants at an early stage of their development, than towards the end of the vegetative stage or during flowering.
* It is always better to prune growing tips in the morning than in the evening, as it gives the plant a full day to recover and heal the wounds.
* It is not recommended that you prune every new node in a developing plant. Rather prune every second or third node to allow the plant time to recover.
* Wait for the new node to start growing before clipping the young branch a few millimeters above the previous node's newly formed leaves.
* It is always better to use a small scissors to prune your plants, than to simply pluck off the growing tips by hand.
* Do not prune any growing tips if you notice that your plant's health is declining and it has started losing leaves. Although you should always smoke the pruned growing tips, plants should be pruned to develop their growth rather than for smoking purposes.
* While it may be tempting to prune female buds during early flowering, your harvest will be severely reduced by doing so.
* Cannabis Indica is a genetically smaller and more bushy plant than Cannabis Sativa and usually requires less pruning.
* Never prune more than the single growing tip, or upper-most node, from any branch on the growing plant.
* The upper-most growing tip of an unpruned marijuana plant will always be more potent that the top buds of a pruned plant grown in similar conditions.
* Pruning the tallest branches ensures that the lower branches grow upwards, forming a larger surface area for the light to cover.
* The clear fluid that often flows from the end of a newly pruned branch, contains substances which seal the wound and aid the healing process.
* Although it is recommended that you remove all dying leaves from the plant, you should resist the temptation to prune too many healthy leaves.
* Another good reason for pruning is to take cuttings from a strong growing, favourite plant for further hydroponic development.
* Marijuana growers often prune their plants in an attempt to limit their height and prevent unwanted detection.
* An alternative to pruning for developing growth, is to bend the tops of the branches over and tie the growing tips down with string or wire.
* Remember that by pruning a growing tip, you are removing the most potent part of the plant, thereby spoiling it's chance of reaching full maturity.
* By pruning all the buds at harvest time, rather than cutting the stem off above the ground, you could easily harvest your plant a second time.
* By severely pruning your marijuana plants you are lowering their resistance to harmful natural enemies such as insects, fungus and frost.
* You can make a great cup of tea, by chopping up some pruned growing tips and soaking them in boiled water for a few minutes.
* Cannabis is a very hardy and adaptable plant, and will endure serious harm to it's leaves, branches and stem before it dies.
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