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Topping marijuana plants

topping marijuana plants

Topping is one of the most commonly used training techniques.

What is Topping ?

Topping involves the removal of the growing tip of your plants. This causes the growing tip to split and form two main kolas instead of one. With multiple topping it is possible to turn your two heads into four, four into eight, and so on.

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Pineapple Kush Topped 2

Not only does topping your plant create more than one main kola.
It also promotes the growth of all the lower branches and vegetation.

Just topping your plant once will turn it into a much bushier shape. With multiple topping in effect what you are doing is reversing the natural Christmas tree shape of the plant. It becomes an upside down Christmas tree with most of the growth at the top of the plant, closer to the light source.

Topping is also important in managing plant height. Once topped, plants will not reach their maximum height but rather fill out more sideways. If the vertical grow space that you have available is limited then topping can help you keep tall leggy plants, like the Hazes, under control.

Topping is also known as ‘pinching out’. This is because many growers do it by pinching out the growing tip between their thumb and forefinger. We always recommend removing the tip with clean, sterilized scissors or a sharp blade.

How Does Topping Work?

Marijuana plants place most of their energy into the main kola, also known as the terminal bud or the apex bud. They do this because the main kola grows bigger, being nearer the light, and represents the best chance that the plant has to become pollinated and reproduce.

To ensure that the plant puts all its energy into this main terminal bud it relies on a strategy known as apical dominance. With apical dominance the highest bud on the plant sends growth suppressing hormones (principally auxin) down to lower bud sites. This keeps the auxiliary buds smaller so that most of the energy that the plant puts into flowering goes straight into the main kola.

When you remove the growing tip of a marijuana plant two new tips emerge from each side of the node just below where you cut it. These tips are now both apex buds and apical dominance applies to them both.

When to Top Marijuana Plants

Plants are ready to top once they have developed 3 or 4 nodes. However, if you wait until the plant has developed around 5 or 6 nodes it will be able to recover more quickly due to its larger photosynthesis area. Some grower prefer to wait until they see roots appearing at the bottom of the pot before topping, to ensure that the plant is well established and able to quickly recover.

The weigh off between early topping and recovery time is something that can vary from plant to plant. Robust vigorous strains like Power Plant can handle early topping whereas some slower growing strains, such as Urkle, will only benefit from topping if you have the time to let them.

Once the main stem has been topped it is possible to repeatedly top new shoots as they form. Simply allow at least one internode to form with a set of leaves and then cut it above that.

Once the lateral branches are established it is also possible to top these, encouraging an overall bushy structure. This is essential when setting up large canopy techniques such as a SCROG set up. A large SCROG may be topped upwards of twenty times to force the plant to form a wide canopy with many growing tips.

When Not to Top Marijuana Plants

Do not top your plants during the flowering phase. When a plant is flowering it completely changes the way that it grows and operates. Nutrient requirements change and the plant really focuses its energy into flower production. Once you have switched to 12/12 topping can cause stress to the plant which is likely to result in smaller yields. If you top during flowering the plant is forced to use energy for repairs that it would have otherwise used for packing out those lovely sticky buds. All the time that it spends repairing itself is time that it is not developing flowers.

How to Top Marijuana Plants

Topping a marijuana plant is a very easy procedure. Firstly, as with all techniques that involve removing part of the plant, make sure that you have clean, sterilized scissors or a sharp blade.

  • Select the plant stem, just below the growing tip;
  • Make a clean cut just above the lower internode;
  • Allow at least one internode to form before topping again.

It really is as simple as that. There are very few circumstances under which topping your marijuana does not result in a bigger yield.

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