If you do it right, pruning your valuable marijuana plants can lead to a much higher yield. It’s one step more advanced than the basics of giving the plants life and keeping them happy and healthy.
It is not something to be done without much thought, planning, or understanding. If you don’t fully know what you’re doing, don’t prune at all.
Some experienced growers will actually never prune their plants. Their philosophy is more about allowing nature to do its thing. They have a good point - without pruning, they are probably doing quite well as marijuana farmers and are completely avoiding the risks that come with pruning.
That being said, pruning in a controlled, moderate way can be extremely useful. When done correctly, pruning in this way can be a crucial way of getting the healthiest, best growing plants with the most THC in your final product.
In this article, I will equip you with the knowledge you need to properly and safely prune your marijuana plants. Keep reading and learn to prune like a pro!
How to prune?
By definition, pruning marijuana is simply the process of clipping pieces of a plant off. If the grower can remove these pieces in small and specific amounts, they will actually achieve a stronger plant.
Especially when taking off parts of the plant that are already dead (such as discolored leaves), it can be compared to removing dead tissue from a human’s wound.
The death of a certain amount of leaves is a normal part of a marijuana plant’s life cycle, and their swift removal could save your plant the resources that are being wasted on dying limbs. These leaves don’t die quickly, so by clipping their stems early, you might be saving your plant weeks of extra effort.
These resources are then focused on more important things, like the still-healthy leaves on the plant, or growing brand new leaves. Because of a more efficient use of resources, the end result will be a larger, healthier plant.
Pruning also encourages new branches to grow on your plants. Once your plant begins having a pair of leaves sprouting from the very top on a daily basis, the topmost leaf will grow some new branches. That’s good news because more branches mean a higher yield.
How to prune?
One way of pruning, you may want to consider is, once these new branches start sprouting leaves, removing the original shade leaves from which they grew. They will yellow and die eventually anyway, so by removing them earlier you can allow your plant to focus its valuable resources on other things.
Removing these leaves also provides more sunlight to the smaller leaves closer to the base of the plant, which gets them to grow faster and produce more chlorophyll.
Before and after pinching
You can also take away the plant’s top, as well as the ends of its branches. This will also help to stimulate branch growth. When you cut off the end of a branch, the growth there will slow down for a while, but then two new branches will come out from that spot.
Tip: make sure to download my free Grow Bible for more information about pruning your plants
It can lead to bushier plants with more branches - and, therefore, more leaves. Some people prefer not to do it since it slows down growth to a certain extent.
When to prune?
You can start thinking about pruning in the second week of the growing phase. At that time, your plant will have several internodes, and you’ll be able to see a bit how it’s growing. If you are growing an Indica plant, wait another week - they grow a bit slower than Sativas.
Since growing continues until the third week of flowering, you can prune up to the second week of flowering. This gives your plants some time to recover. They’ll always need a couple of days to recover after a pruning session.
When to prune?
It’s even possible that they stop growing during this period because all their energy is focused on recovery. Since you want as much energy as possible to go to the buds, do not prune after the first two weeks of the flowering period.
Until then, remove about a quarter of the new side shoots every week. Be sure to leave the older leaves and twigs, because they produce a lot of sugars. You also should ensure you keep enough fully grown leaf surface. They produce sugar and prevent light from being lost by falling to the ground.
You will need to decide which of the following pruning methods will be best for you. Each one comes with its own set of challenges and benefits, so choose carefully. You can also sometimes use more than one method together to form a combined plan of sorts. Keep reading to learn the advantages of using certain pruning techniques.
How to top marijuana plants?
Topping marijuana plants involves cutting off the main shoot at the top, thus stimulating the growth of more shoots and branches. Over time, it will turn the plant’s overall shape into a downward-facing cone, which will help your plant maximize the sunlight that it receives.
This is especially important if you have a grow room indoors since your light is limited (and expensive) compared to natural sunlight.
You can decide to start topping as soon as your plant seems strong enough. Check for the secondary growth that is located near the low nodes - this is a reliable sign that your plant can withstand topping.
How to Top?
Here is why topping works - a shoot grows into 2 new petioles with leaves on them. The middle of the shoot contains a new shoot, and new shoots will be formed in the axils. A shoot, therefore, consists of 2x2 leaves, crosswise against each other. By removing this, the two shoots in the axils will grow to become the main buds.
Note: After your plant’s fifth leaf pair has popped up, you can safely cut off the main shoot
When you are topping, make sure you only cut the latest shoot, so you only inflict minimal damage to the plant. It’s important to remember that your plant is damaged, so it will use its energy to heal the wound, and won’t grow much for a couple of days.
You can top multiple times if you want to, but remember to leave some time in between sessions, so the plant can recover. Topping is always done during the growing phase, and possibly in the first week of flowering at the very latest. Otherwise, the plant has no time to grow wider, making the practice a waste of your time and your plant’s energy. More about this in my free marijuana grow bible
Why should you top?
Topping is useful if your growing room isn’t very tall. Sativas can grow very quickly and can become very tall, so it is especially useful for them. Since they don’t get very wide, you have to place many plants close to each other, to prevent wasted light. The light that doesn’t hit the leaves and falls on the ground is considered lost energy.
By topping your plants, they will stop growing up and start growing out. Because of this, you can leave more room between plants and still have a beautiful green blanket. Don’t bother topping Indicas, they grow much slower, and take too long.
Another advantage of topping is that the plant can absorb more light. This is because it becomes wider and develops more leaves that can absorb the light. This can significantly increase yield - especially outdoors. It also applies to indoor plants, but it’s easier to use more plants to prevent light loss, rather than topping.
Lastly, topping also spreads your risks of disease. Since the process produces more main buds that are not as big, they’re not as sensitive to bud rot and/or other nasty diseases. This is mostly an advantage for outdoor plants, where growers can’t control the climate. Indoor growers have it easy, they can simply place more plants and not worry about topping.
Topping result after 3 weeks
Again, be careful with the big, heavy plants, because there’s a chance that the plant will split in half under its own weight. It’s best to strengthen the plant with some tape, just under the topping, to prevent splitting. Once again, this concern is more for outdoor plants.
Fimming is the partial removal of the latest shoot of a plant. When done, it creates four main buds instead of one.
A fimmed plant is wider than and not as tall as a typical plant. It also has more leaves exposed to light, causing more light to be absorbed. While the process damages the plant a bit, most recover quite well, making it a useful method of increasing yield.
How to Fim?
After it is cut, the shoot grows into 2 new petioles, each with their own leaf. The middle of the shoot contains a new shoot, and new shoots will be formed in the axils. A shoot, therefore, consists of 2x2 leaves, crosswise against each other.
By removing two-thirds of it, you’re only cutting off the leaves, while leaving the stems. These will, along with the shoots in the axils, grow to become main buds. So, you end up with four main buds. Make sure you don’t cut off too much, or you’ll only end up with two main buds.
Note: I never fim Indicas; they grow too slow, and the vegetative stage would last too long
Fimming damages the plant, and it will use its energy to heal the wound so this can slow down the growth a bit. You may also notice that the newest pair of leaves are damaged when it starts to grow, but this is normal.
Leaf damage after fimming
You can fim multiple times, but leave some time in between fimming sessions for recovery. Fim during the growing phase and possibly the first week of flowering at the very latest. Otherwise, the plant has no time to grow wider, completely defeating the purpose.
Why should you fim?
If your grow room isn’t very tall, fimming is very useful. In the case of Sativas, they grow very quickly and can become very tall. Fimming helps them grow wider instead of taller.
Fimming also helps your plants absorb more light. Since they don’t get very wide, Sativas are placed close to each other to use all of the light. The light that doesn’t hit the leaves and falls on the ground is considered lost energy.
When fimming, the plants temporarily stop growing lengthwise and mainly grow in width. Now, you can then leave some more room between plants while maintaining a nice green blanket of leaves.
Fimming results after 5 days
Plants that have more leaves that can absorb light will produce a greater yield, and the fimming process increases light exposure to leaves. Fimming is especially useful outdoors and is the secret behind those gigantic outdoor plants featured in pictures. It also works for indoor plants, but it is easier to use additional plants to make sure no light is lost.
It’s important to mention the fact that fimming spreads your risk of disease. Instead of a few big buds getting ruined, the process produces more main buds, and because they’re not as big, they’re not as sensitive to bud rot and/or other nasty diseases. Once again, this is a significant advantage for outdoor plants.
Tip: make sure to download my free Grow Bible for more information about pruning your plants
These plants have fewer defenses since you can’t control the climate and the moist fall air is perfect for bud rot. Indoor growers can simply place more plants without fimming them to spread the risks.
Be careful if you have a gigantic, heavy plant because there’s a chance that the plant will split in half under its own weight. It’s best to start strengthening the plant with some tape, just under the fimming, to prevent splitting. This only applies to outdoor plants, because they get much bigger and heavier than indoor plants.
The basic idea behind super cropping is crushing the stem’s soft interior. When done correctly, super cropping should stimulate health, bring a higher yield, and increase potency.
Just like with any injury, animal or plant, breaking the tissue down will cause it to be rebuilt more strongly. When you crush the inside of the stem (which is where nutrients and water are transported), it will be rebuilt thicker and stronger, allowing for even more efficient transport for these key elements.
How to Super crop?
The whole plant will become healthier if you pinch the center stem. If you pinch the branches on the side, you can control the shape of your plant. You can simply (and gently) bend the branch in whatever direction you want it to grow.
Super Cropping Tutorial by Med Grow Cannabis
The best time to carry out super cropping is the second or third week of your plant’s vegetation stage. Simply pinch and twist the branch simultaneously between your thumb and pointer finger, and bend the branch (without breaking it).
Let it go as soon as you’ve felt it give way; even if it droops a bit, it will heal in time. Read the article Super cropping marijuana plants for more info
Low stress training
The letters “LST” stand for “Low Stress Training.” Topping and super cropping are methods that can be considered opposite - they are High Stress Training or HST.
LST is a safer option than HST since HST actually damages the plant at first. That being said, you can combine topping and LST training nicely (although plenty of successful growers choose the LST-only route and don’t do any topping at all).
How to Low Stress Training?
LST is a type of pruning (or, more accurately, a type of training) that involves tying down your marijuana plant, thus stimulating the growth of all the shoots newly placed above the main stalk. This is because your plant has been tricked into thinking it no longer has a main shoot, meaning it prioritizes its resources into growing its other stems faster.
This will allow your plant to become denser and bushier. The key thing to remember with this method is to never rush. This is a technique that takes time and patience, and anyone who tries to do it too quickly will have poor results.
There are many other techniques out there for savvy growers, so if you are interested you should do some more research to find out what the perfect pruning technique is for you. There are also other ways of “training” your plant that could come in handy, so make sure you know all of your options before beginning. Read the article Low stress training marijuana plants for more info.
Monster Cropping (a.k.a. flowering clones) is new method of growing that one of our members brought to my attention. Monster Cropping essentially involves taking clones from flowering marijuana plants, and then rooting those clones.
They will reenter vegetative state and eventually create super-bushy plants with a large amount of nodes and branches. This method was dubbed “Monster Cropping,” because that’s exactly what you’ll end up with—huge, monster plants.
Flowering plants typically aren’t a source for clones, and most experts will tell you that it goes against most rules of cannabis cultivation. Even so, the science behind Monster Cropping is legitimate, and you will certainly enjoy the results. Read the article Monster cropping marijuana plants for more info
Lollipopping is a technique that removes the lower growth of your plants to promote better bud development on the top. By eliminating the competing growth, energy is directed to the main kola sites. This technique is especially useful in setups that have no side lighting to reach the lower regions of the plant.
The main idea behind lollipopping is simple. Remove the overly shaded parts of the plant that are unlikely to be productive. Then, force the plant’s energy to bypass these sites and go straight into producing larger colas.
Removing the lower bushier growth can also improve air circulation around the bottom parts of the plant where humidity often builds up, especially after watering. For bushy plants that are susceptible to mold or other fungal infections, it lowers their risk. It also useful when growing outdoors in damp climates.
When to Lollipop
This also is a controversial topic. Most growers agree that lollipopping should take place during the veg phase. It can be done as a continuous process or all in one go but do so around a couple of weeks before you being the 12 hours of light/12 hours of darkness. This way, your plants have time to recover from the shock you just put them through before beginning their flowering mode.
Some people believe you should never lollipop once the plant has started flowering. However, as long as the main work is done during the vegetative stage, you can do some light maintenance during the flowering period. You may want to prune those branches that haven’t quite made it to the canopy or remove the tiny popcorn buds that begin to form on the bare lower branches.
How to Lollipop
There are basically two ways to lollipop your plants; which one you use will depend on the results you seek.
Technique #1 – Top Down Lollipopping
It’s called ‘lollipop’ because of the shape of the plant once you have finished with it. When the lower growth is removed, all that remains is a plant with a long bare stem and one or more large colas on top. (However, this may vary a bit, depending on if you used other techniques.)
While many growers consider this technique to be extreme, it is a quite simple process. Choose a point that’s about 4 nodes down from the growing tip of the plant, (or wherever you want the canopy growth to begin), then remove the growth from the main stem below that point.
To remove the growth, simply grasp the main stem between thumb and forefinger and slide downwards, taking the side shoots with you as you go. It’s a simple step, but be careful not to damage the main stem. It’s best to use a clean, sharp blade or scissors.
Technique #2 – Bottom Up Lollipopping
This is a not as severe a form of lollipopping – perhaps even, a “lollipopping lite.” It is also the most common way to lollipop marijuana plants. Check out these pictures by thenug.com
To do the bottom up method, start at the bottom and work upwards. Remove short main lateral branches and any leaves on the lateral branches. If they are too short to make the top of the canopy, they should go. In the end, the bottom third of the plant should be bare of any growth. This type of lollipopping often requires some maintenance trimming while the plant grows. You’d use this kind of technique when SCROG growing.
There are some benefits to pruning. When done correctly, it can improve sugar distribution and increase your yield. I recommend pruning young leaves or side shoots. The tiny buds at the bottom of the plant are a great thing to let go as they do not yield anything worthwhile and won’t grow to the size of other buds. They will use energy, however, which a waste since you won’t use them.
Don't prune large fan leaves. Plants produce sugar so they can grow, and a marijuana plant needs to produce a lot of it. It creates sugar by converting water, light, and CO2. This process also creates oxygen. This sugar is sent to the buds, side shoots, and young leaves because they grow quickly and use a lot of sugar. The larger, fully-developed leaves produce their sugar.
Note: Pruning can be harmful to your plant and lower your yield if you don’t know what you are doing, so don’t if you are new to growing
If you are new to growing (less than three times), now is not the time to start. Take some time to learn what a fully-grown plant looks like first. Look for the buds at the bottom of the plant.
If you’ve already grown a few times, try pruning a couple of plants. Don’t prune them all - that way you can compare your pruned plants to the plants you haven’t pruned.
Most importantly, don’t expect to master this technique the first time you do it. Pruning is something you do intuitively. If done correctly you can increase your yield with 25%
Plenty of new, excited growers make the mistake of overpruning their cannabis plants. This can often happen because these new growers want to take off as many THC-filled leaves as possible, even before harvest time.
It’s true that you will probably get more enjoyment from it than from buying a bag of pot in the meantime, but you must proceed with caution. Remember: the best weed won’t come until it’s actually harvest time. You must not do anything that could slow down growth and reduce the productivity of the flowering stage.
There are a few things to avoid when you are pruning your plants. First of all, if there are no branches growing out of a leaf’s basal stem, never cut that leaf off. Don’t strip one branch or stalk of all its leaves.
When pruning, don’t tear a leaf away with your hands; rather, cut them with scissors or a knife (make sure your tool of choice is quite sharp before use, check these pruning tools).
It is also important to remember to water your plant immediately after pruning it. It will reduce the amount of shock to your plant, and will stimulate growth. This will be especially effective if you include plant food when watering. If you follow this advice, you will be able to prune in a productive, helpful way rather than harming your plant or slowing down its growth.
Unfortunately, any leaves that you prune when your plants are less than 3 months old will not be very smokable. This may feel like a waste, but remember that the point of pruning is not to have an early stock of weed, but rather to improve your overall yield in the end.
The reason your plants won’t have enough THC until they are three months old is for an ingenious reason. In general, leaf-eating bugs typically start becoming active (and hungry) roughly three months into the growing season. Because THC repels insects, this is around the time when marijuana plants need to have lots of THC to keep those hungry bugs away. Therefore, they increase their levels of THC around the three-month mark.
If you are really curious and impatient, you can go ahead and try smoking some leaves earlier than mid-July, but don’t be disappointed when it doesn’t end with a successful high. You will, therefore, have to throw away most leaves that you prune, but make sure you do even that with care. Burning is the best option, since it won’t leave any evidence of your marijuana possession.
If you are planning on jumping into the growing scene without proper research, be very aware of the fact that there is no guarantee for success. Sometimes even a fully mature marijuana plant’s buds won’t have enough THC to achieve a high. This will only occur when the plants are improperly tended, so as long as you do the proper research and tend your plants responsibly, it should not happen to you.
If you want to be extremely cautious, you should only prune the leaves that already look unhealthy. If they are turning yellow or have brown tips, if their lobes are partially eaten, and if they are withered at all, you can (and should) safely remove those leaves. When the bases of leaves have branches coming out of them, you can remove those leaves. Always begin with leaves that are the highest up, as this will encourage smaller leaves down below to speed up their growth.
Responsible, strategic pruning will allow your plant to enhance its ability to produce THC and repel insects. It will increase your yield in the end, and could provide you with some weed to smoke in the meantime. All in all, when done responsibly, pruning your plants could be a very wise decision for you.
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