Topping your cannabis plants is a totally free and amazingly easy way to double, quadruple, or even octuple (that's an increase of eight times) the number of main colas that each plant produces.
The list of marijuana plant training techniques is extensive, to say the least, but topping (while considered somewhat 'advanced') is actually pretty straightforward and should be in your bag of cultivation tricks from the day you begin your weed-growing adventure. All you need is a weed plant that has 4 to 6 nodes already developed, a pair of clean scissors or a razor blade, and just a light sprinkling of know-how - which is what you are here to learn, right?
So, without any more pussyfooting about, let's get into it.
What happens to a cannabis plant when you top it?
A few things.
We all know what an untouched weed plant looks like. When left to their own devices and allowed to grow as mother nature intended, cannabis plants grow in a 'Christmas tree' like shape.
This growth pattern (known as apical dominance), which is seen throughout the plant kingdom, isn't just for looks - it's actually a great way to direct the plant's energy into producing seeds and fruit - or, in the case of weed plants, one huge juicy main flower, with some secondary, less luscious buds growing on the branches.
But we don't want that. What we want is more 'main colas'.
You see, when we leave the pot trees to do as they please, the bud growing at the tip of the main stem (the main cola) receives the lion's share of growth hormones, more nutrients than other budding sites, and also gets the most light. This results in this top bud swelling to enormous sizes and being responsible for the vast majority of your harvest.
When we top a weed plant (or any plant that can be topped, for that matter—I topped my basil plant a few months ago, and the results are amazing), we cut the main stem just above one of the nodes. The nodes are where the branches attach to the main stem, and by removing everything above the node, we force the plant to make those developing branches the new 'main stems'.
So, instead of one huge bud developing, you now have two! And, even better, you can then top the new 'main stems' again, giving you four main colas! And again! Eight main colas, or even sixteen if you have the time!
You might see a pattern forming there, yeah? Each time you top the new 'main stems', you double the number of 'main colas' it is able to produce.
Does topping weed plants help in any other way?
Yes, by breaking the apical dominance through topping, we also force the plant out of its vertical (or upward) growth pattern and into a more horizontal (or outward) growth pattern. With a little bit of knowledge and some soft plant ties, you can easily create a topped plant where all the 'main colas' are at the same height.
This means your plants start to 'open up', with more light reaching all parts of the plant, leading to healthier and lusher foliage, which in turn leads to better bud development. This also boost the amount of air circulation and exchange in the canopy area, bringing more CO2 to the plants. This also leads to better harvests, and much lower chances of pests or mold becoming an issue.
How should you top cannabis plants?
First things first, you need to grab just a few bits of equipment. You'll need a clean and sharp pair of scissors or a razor blade, rubbing alcohol (or another disinfectant), some paper towels, and some sort of plant ties—soft gardening wire is perfect. Then it's just about getting after it!
Find the ideal candidate
Look for the perfect plant to top. This should be one with four to six nodes already formed, a healthy and thick main stem, and a healthy plant generally. Topping imparts a decent amount of stress on the plant, so don't top plants that are already having a tough time. Having at least four nodes already developed is important, as we don't want to top plants that are too young to handle the stress.
It is also extremely important to only top plants that are still in the vegetative growth stage. Topping a flowering cannabis plant will just mean cutting away the flowering sites, not increasing them.
Prepare your tools
Before you start cutting, make sure your scissors or razor blade are super clean, and you might even want to grab a pair of latex or medical gloves. Remember, you are cutting a decent chunk of the plant away, so treat it like you would when you take a trip to the doctors. Disinfecting your tools with rubbing alcohol is a must do.
Where do you cut when you top cannabis?
Now that you have everything ready and your tools are clean, it's time to make the cut.
You want to cut just above the 4th, 5th, or 6th node - while also being super careful not to damage the baby branches that are starting to emerge from the node you just cut above. Remember that they are about to become the 'main stems', so take all the care you can, not to damage them.
Also, try to make the cut as clean and precise as possible. A jagged or torn cut will take longer to heal than a nice, clean cut and can lead to infections in your plant. As long as you use sharp, freshly disinfected scissors, you shouldn't have anything to worry about.
Can I top a weed plant more than once?
You sure can, and if you have a few weeks left of vegetative growth before the plants switch to flower production, then you should! As we mentioned before, each time you top a plant, you double the number of main colas it can produce.
So, if your plants have enough time to recover and grow new branches before flowering starts, go for it! Just remember only to top once per 10 days or so and let the plant recover in between. Any more than that will be too stressful for the plant, and you could heavily stunt growth or even kill it.
Can you top autoflowers?
Yes, you can top autoflowering cannabis strains - but should you?
Probably not!
Unless you know the strain inside and out, and you are sure that it has the time to bounce back and flourish during vegetative growth (keep in mind that autos only have a few weeks of veg before they automatically switch to flowering growth), then it is usually best to just let them grow naturally.
Topping can definitely increase yields, but only if done correctly and at the right time. When you are growing autoflower seeds, it can be tricky to get topping right, so it's best to err on the safe side and let them grow as they please. Most autos only have around 3 to 4 weeks of vegetative growth time, so any stress during this period can significantly impact their final yield.
Topping vs LST which is best?
It's not a case of either, but both!
If you are growing with feminized seeds, you should definitely also implement some LST. These two plant training techniques were born to be together.
What is LST?
LST, or 'Low-Stress Training,' is a plant training technique that involves using plant ties or twine (or any other soft material) to gently pull the stems of your plants down and away from the center of the plant.
By doing this, you create a wider, more horizontally even canopy - This allows for a much more even spread of light and better airflow in and around the growing buds.
Topping vs fimming: What is the difference?
They are almost the same thing, with one major difference...
'FIM' stands for F***, I MISSED. Missed what?
Well, it means that when you topped your plants, you missed the new growth point at the very top of each stem and instead cut 'through' it at a 45-degree angle. It can also be done by 'pinching' instead of cutting, but this is a lot harder to get right.
For the vast majority of you out there, we DO NOT recommend trying fimming. While it can result in more 'main colas' being produced, it often doesn't. It is easy to get wrong, and with topping being such a consistent and easy way to increase yields, it's not worth the risk.
If you stick to topping and LST, you heavily reduce the risk of anything major going wrong, and you can be sure to walk away knowing that your precious weed babies should make it to the end of flower and be ready for harvest without any hiccups.
The wrap up
Topping weed plants is a fantastic way to increase the yield potential of your cannabis crop and control the height, light spread and penetration, and air exchange in and out of the canopy. These benefits all come with side benefits, like creating a more even plant canopy, reducing the risk of pests and mold, and allowing all the budding sites a chance at receiving an even amount of light - resulting in bigger, better buds all around.
You are now armed with all the info needed to top your cannabis plants with confidence. So go ahead and give it a try, and watch as your plants turn into bushy, beautiful monsters! Just remember to be patient with them and let them recover in between any topping sessions.
As we always say, growing weed is meant to be fun. Don't take it too seriously - experiment and find what works best for you!
