TOPPING VS FIMMING: Cannabis Pruning

Written by on 12 January, 2022

If you want to get a crop of very dense, resin-filled buds, the type of pruning you do plays a very important role. The two best-known types of cannabis pruning are apical pruning, known as TOPPING, and fim pruning, known as FIMMING.

We explain to you what the 2 versions of pruning are.


Apical pruning or topping consists of making a cut at the tip of the main stem of the Cannabis plant. It is possibly the most widely used high-stress training technique, or HST, in both indoor and outdoor cultivation.

Naturally growing cannabis usually looks like a Christmas tree, with a central stem and several side branches. With this morphology, all areas of the plant will receive the same dose of light as the sun crosses the sky.

However, indoor things change. In indoor cannabis cultivation, the light is generated by fixed, non-moving growing foci that are above the plant. This makes the natural shape of the plant ineffective, unless we grow large crops using the SOG or See of Green method.

Apical pruning of cannabis is the procedure most often used by professional growers as it is able to increase the yield quite a bit.


The way to make the little apical or topping is to make a clean cut at the tip of the main stem with scissors that have been sterilized previously.

We must cut the tip at 100% so that the tail will become two. The best thing of all is that we can carry out this technique several times, that is to say, we can multiply the tails.

Usually, it is done early when the plant has 3-5 knots. However, there are growers who say that you should wait a bit and do it after 30 days, or until the plants are at least 30cm high, before doing the pruning.


Fimming is a high-stress procedure that increases yields, and is similar to topping, although it has a number of variations.

As with apical pruning, the aim is to increase the number of main tails, but instead of doubling them, with FIM pruning more than 4 new tails can be generated. This procedure is recommended for micro-producers who only want to have 1-2 plants.

With this technique, the secondary shoots will take advantage of the growth hormone that was previously used to “feed” the main stem. Most growers think that FIM pruning is a little less effective than apical pruning in decreasing the stretch.


In the same way as a topping, it is best to perform this procedure when the vegetative development stage takes place. However, unlike apical pruning, this procedure has a less precise approach.

To be more explicit, FIM comes from the acronym of the expression “Fuck I Missed” which means “Fuck, I failed”

With this method, it is preferable to remove 75% of the main stem tip with your fingers than to make a clean cut of the entire tip.

Aesthetically, it is very nice, but it is effective.  At least 4 new shoots will emerge after one or two weeks. Sometimes up to a maximum of 8 new shoots can be generated. In addition, secondary shoots will gain ground at the same time.

NOW! Are you ready to prune your most precious plants?

Current track