FIMMING Cannabis Explained

When growing cannabis, there are a number of techniques that can be applied when shaping the growth structure of your plants. Below we cover a technique that was somewhat created by mistake and even given a name to remind us known as FIMMING.

What Is FIMMING?

To keep it as simple as possible, FIMMING means attempting to top a cannabis plant to create two crown shoots, but accidentally or purposely leaving enough growth behind. If you’re wondering where this name came from, then add “Fuck I Missed! “into the equation and you will probably figure out the origin!

When FIMMING occurs, apical dominance ceases to a halt and while the plant will not create two crown shoots as originally intended, the growth energy is now exerted to the rest of the lower plant. As a result, the growth structure will become bushier and the lowest parts will begin to grow with more dominance than prior to the removal of the top shoot. When the FIMMING technique is successfully applied, 20%-30% of the original growth will have been left behind.

What Happens to The Plant?

The growth hormone Auxin that is responsible for apical dominance is dramatically reduced. As cannabis is one of many plant varieties on Earth that grows a main central cola. The manipulation of the canopy during the growing phase will have a direct effect on the biochemistry of your cannabis plants.

Once FIMMING is complete, the natural instinct for the plant to grow with apical dominance will no longer exist, meaning the new growth structure will have shorter, denser characteristics in comparison to a cannabis plant that is left to produce Auxin. The plant is simply left to grow back until the original FIMMED top growth is now growing in synchronicity with the rest of the plant.

Does FIMMING have any benefits?

Each individual plant training technique has its own benefits when applied at the right time, to the right strain, with the ideal skill and experience level. FIMMING is an excellent way to reduce plant height and focus on lateral growth, which is particularly useful when working with a small indoor grow space, or growing outdoors and trying to keep the initial height down before flowering starts.

When Should I Apply FIMMING?

All plant training should be done when Cannabis plants are in the growing/vegetation phase. This is when they are indoors under 18/6, or outdoors during the Spring and Summer months. FIMMING during the early stages and until the last parts of the growing phase will allow a grower to produce a very thick plant that when flowered should produce quality buds from top to bottom.

Applying FIMMING after the flowering cycle has commenced will cause stress to your plants, and may even lead to hermaphrodites. Plants will stretch during the flowering phase and any attempt to control this in advance should be done so then. This should never be carried out when your plants are transitioning from the growing phase.

FIM Step by Step:

FIMMING Vs Topping
FIMMING Vs Topping

To perform the FIMMING technique, you will only need a clean, sterile pair of scissors and a candidate plant. A sharp pair of scissors is recommended to allow you to make the cut as accurately as possible.

Step 1:

Take your plant and scissors and find a place with good lighting so you can clearly see. Never perform this technique in low lighting as you may end up topping the plants or leaving far too little on.

Top Tip: Use a grow light to illuminate the plants and carry out this technique inside the grow tent

Step 2:

Take the very top crown shoot and visually mark the tip and line your scissors up to reveal the 30% of growth that will be left behind. You can do this will a ruler or any other type of marker.

Top Tip: If you are new to FIMMING, aim to cut 40% of the leaf tissue off.

Step 3:

FIMMING Growth

Once you are happy, take the scissors and cut horizontally removing 70% of the growing tip in one smooth cut. Avoid thick scissors or blunt ones, that cannot get the clean cut you need.

Top Tip: Use sharp scissors and the smaller the better to get precise cuts. Thick scissors can remove more than you may intend.

Step 4:

The top will look closed up and should be left alone and not touched until it can grow back over the next 7-10 days. Naturally as the plant recovers you will notice an abundance of lower growth and enhanced vigour.

Top Tip: Do not attempt to FIM again, or touch the FIMMED top and leave the top to grow back and recover.

Step 5:

After 7-10 days the new growth will resemble a normal leaf set and you would never know it had been FIMMED. Once the plant reaches this point you will now have a bushy, dense growth structure that can trained further, or ready to be flowered under a 12/12 cycle.

Top Tip: You can perform this technique on multiple shoots at once after your canopy takes shape.

Have you tried FIMMING? Tell us in the comments below.

About Stoney Tark

imageStoney Tark is head writer for Soft Secrets, High Times Magazine and Weed World. He is also the main breeder and owner of Prana Medical Seeds.

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