Removing the main crown shoot of your growing tip will ensure that two new shoots will grow back in its place. Pinching out once will create two tops; pinching out twice will create four tops; and so on. This technique is as simple as cleanly removing the growth tip until a lighter, fleshy-colored part of the plant tissue is exposed.
This will heal over and then form new growth shoots. It is very important to create a clean cut to avoid “fimming” (see below). I personally like to use a clean pair of nail cutters and to really get in and cut as close as possible. When incorporating a screen into the garden, topping is essential in creating a symmetrical canopy base from which to work.
Benefits: A plant’s height is basically cut in half-instead of one tall plant, the plant is separated into two parts. With this technique, the growth hormone that is responsible for apical dominance-in which a plant’s central stem is dominant-is cut off and a new hormone is emitted that promotes lateral growth. When the canopy is pinched out until the plant is flat-topped and multi-branched, canopy control is at its maximum.
Topping plants out will produce a greater number of smaller-size colas, as opposed to a main cola with supporting side branches if left untrained. This technique is ideal for growers who have limited space and want to avoid tall, lanky plants, and those growing plants with long vegetative periods, as this technique will produce a vibrant plant with eight heads in about 4-5 weeks.
When fimming, 80 percent of the crown shoot is removed, with a very small amount left behind. In response, the plant will cease to produce upper growth, focusing its energy on the rest of itself underneath the highest part where it has been fimmed. Growth at the low part of the plant, from the very base of the pot and each internode upward, will increase, creating a thicker-looking plant. To use this technique, simply take a pair of scissors and snip away three-quarters of the tip of the crown shoot of the main cola or on the top shoots of the supporting side branches. “Fimming” is short for “Fuck, I missed!” because the technique was discovered by accident.
Benefits: Plants will have time to focus on enhancing the growth tips that are below the fimmed shoot. The lowest buds will have a chance to catch up with the rest of the upper growth, so when the top shoot does grow back to normal, the entire plant has increased in size. Fimming can create really bushy plants, and it can help avoid weak-producing lower buds.
This is my favorite technique for pushing my plants to the limit. It’s a hands-on high-stress method that involves breaking the inner cell walls of a branch by popping it between your fingers. When successfully performing this technique, you’ll be able to hear an audible snap as the plant’s inner walls collapse-or at least feel a change in the pressure inside the plant.
With young softwood plants, popping the center parts of each internode will suffice; however, with plants that are more woody, it’s much easier to twist and a bend, and there’s a quicker healing response.
Benefits: If you have ever seen a plant that has an almost-round, knuckle-shaped growth forming over a bent branch, it’s been super-cropped. Once the inner cell walls in a branch collapse, growth hormones are sent to the break.
The result is a hardwood, protective growth that will not only provide added support, it will also boost the plant’s vigor and ability to respond to stress. A plant that has been super-cropped will be noticeably stronger in terms of vigor, stature and overall yield.
Otherwise known as low-stress training (LST), this technique involves tying and bending certain parts of the plant at certain times to compel the canopy to grow symmetrically. This technique involves tying the plant down with string or metal cables and lowering the highest point of the crown shoot. The plant will respond with the rest of the growth tips now competing to produce the main cola. Through careful calculation and planning, a grower can simply use leverage to compel the plant to form into a short and stout bush in which the main cola is unidentifiable come flowering time.
Benefits: The benefit of LST is that the canopy will be round with heavy side branches. Additionally, as the plant grows sideways, the axillary shoots that would’ve once produced small flowering sites will not grow upward and toward the light.
The end result comes down to how many times the plant’s been tied down to create new vertical shoots. This technique is also very important when using a screen, and it’s a great way to make those once tiny nugs into main colas.
Referred to as screen of green or ScrOG, this technique involves the application of a screen or net to act as a trellis through which your upper canopy will grow while clearing away the lowest part of the plant below the screen, ensuring a maximum yield of symmetrical flowering sites.
This method requires longer vegetative times than other plant-training techniques, as selected shoots must be fed through the screen over the growing phase. Making a screen is as simple as laying chicken wire over a wooden frame, tying bamboo shoots together in a square formation or even using wire or pea netting.
Benefits: Using a screen not only allows the grower to be totally hands-on with his plants; it also allows those with very small plant counts to achieve large yields in a small grow space. The plants have no choice but to dedicate all their growth above the screen, resulting in no low-hanging schwag buds and improved air flow below the canopy.
Getting rid of fan leaves and low-growing tips is something that all growers should consider doing, but only at the proper time. Plants use their energy on whatever growth there is, so knowing when to cut away and strip the parts that are less productive than the upper parts is important. Take a pair of scissors and, as if you were taking clones, cut away the lowest growth of the plant that will take away from the prize buds you desire.
You should cut away everything from side branches to big healthy fan leaves. A good rule of thumb is to remove around 60 to 70 percent of the growth from the base of pots upward. You can also use your finger and thumb to strip away from the branches. Be vigilant to check for any new growth forming where the pruning took place.
Benefits: During the flowering stage, plants will exhibit the lollipop effect, where the main central stem has been stripped bare under a healthy, vibrant top canopy.
If you don’t prune the lowest parts of the plants, you’ll always struggle with the low-producing, light-deprived growth.
By clearing away a large proportion of the lowest plant parts, you can be assured that during the blooming phase the plant’s energy is being used as efficiently as possible and is focused on the heavy nugs on top. Pruning can make a big difference in the overall production of a cannabis plant, ranging from flower size to overall consistency.
This technique is slightly more complicated than traditional low-stress training, and it focuses solely on symmetrical plant growth. The principle behind mainlining is to remove the top shoot and all of a plant’s lower growth to create a bare stem. This allows the two axillary shoots to grow upward to form two primary shoots. If you picture a capital-Y shape and then grow from this starting figure, you can then tie the two shoots down to allow them to grow in a letter-T figure.
Benefits: Although it can seem like a very stressful training method and can certainly feel counterproductive, the important thing is to stick with it. Due to a carefully arranged symmetrical design, the plant will send signals to each pathway to make sure that each bud flowers and grows the same as all the others. The end result can be very impressive, but keep in mind that this method is for more experienced gardeners and requires much patience.
This method involves pruning away everything underneath the top internode of the plant’s branches a few days before flowering. This focuses all the plant’s energy into the remaining nodes. A full-scale prune can be quite drastic, and it’s the last thing anyone would do to their precious plants, yet this technique works. What’s left is a very skinny-looking structure with only one top shoot, but when it flowers it grows quite top-heavy.
Benefits: This technique removes the risk of any lower-producing popcorn nugs, provides an excellent opportunity to take some healthy cuttings for future grows, improves air flow and reduces insect and pest infestations. The flowers that the plant produces will be thick and dense. The end result will be uniform nugs that are each around 3-5 inches in size with substantial biomass.
Growing large-size plants that take up quite a bit of room requires long vegetative periods to produce as much productive foliage as possible. One can argue about which method produces larger yields: one large plant or many smaller plants under the same grow light. My tip here is to dedicate a grow tent for one or two very large plants. Avoid vegging many plants in a tent as they’ll fight for light and overshadow one another as blooming commences.
You may have purchased a 10-pack of the latest and greatest genetics, and although you calculate that planting 9 seeds under a 600-watt lamp will result in a 9-ounce yield, it really depends on the integrity of your lighting setup. Grow lights are measured in lumen count and photosynthetic active radiation (PAR). My tip here is to find out the amount of PAR your lights are emitting, then work out if it’s adequate enough to produce heavy-yielding plants.
This method requires very short vegging times and a quick introduction to flowering.
The principle behind SOG is to grow as many small plants as possible in a limited space. The turnaround time may be a week longer than the flowering period for commercial growers. Make sure the strain you’re growing is well suited for a SOG grow (such as a short-flowering /nd/’ca-dominant variety) to make the process as straightforward as possible.
There are many varieties of cannabis on the market these days, each displaying traits of indica, sativa or a mixture of both. Growing indica-dominant varieties will allow a grower to produce smaller-size plants. Hybrids can extend taller, and saf/Va-dominant strains will tend to stretch out even more. My tip here is to learn as much as possible about the strain you’re growing. It can determine a short or long vegging period, as well as if SOG or ScrOG is the right method to use.
If you’re new to growing cannabis, it’s better to grow a few smaller-size plants at first to learn the ways of the plant. If you’re more experienced, then generally having a larger plant is the norm, and the level of plant training that can be provided will result in a huge difference in terms of canopy control and final yield. A shorter vegetative time is more forgiving to the beginner, providing less time
to make catastrophic mistakes. Grow according to your skill level in terms of plant count, strain selection and nutrient use.
Your plant count and vegging time may be limited due to your budget; for example, electricity costs soar during the longer 18-hour lights-on periods. You may also be limited in nutrients and prefer to flower as soon as possible to save more during the growing stage. You may also be restricted to pot size, lighting capacity and many other things due to financial restrictions, so plan ahead to spend and grow within your time and financial constraints.
For growers who have a vegging tent and a flowering tent, growing larger plants is probably not necessary, as a constant rotation of smaller-size plants is beneficial and practical. Invest in a tent solely for growing seedlings and clones until they are mature enough to be transferred to the flowering tent.
With the above options for training your plants, you’ll be able to find a technique that is well-suited for your individual space, time and financial considerations. Experiment and have fun-when harvest time comes around you’ll have some dank nugs to celebrate with and begin to plan your next grow!
Originally published in the March, 2019 issue of High Times magazine. Subscribe right here.
Originally appeared in: https://hightimes.com/grow/plant-training-techniques-explained/