Select Page
Mainlining is a technique that has recently become popular, it is also called ‘fluxing‘ and has been used to increase yields throughout many grow rooms. In this 20 minutes mainlining tutorial from Grow420Guide, you will learn how to mainline your plants as well as when to do this technique. You see how this method is performed on a White Cookies female plant, below is a step by step instruction guide based on this tutorial.


  • Top the plant after the 3rd internode.
Mainlining Step 1
  • Remove the lower branches from where the branch forms a V-shape.
Mainlining Step 2
  • Clear away any large fan leaves.
  • Remove all growth until the top head.
Mainlining Step 3
  • Attach screws to the pot where the branch will be tied.
Mainlining Step 4
  • Slip a piece of string over the screw head and tie the branches down until they are horizontal.
  • Supercrop the lowest 2 branches once tied down.
Mainlining Step 5

When To Top The Plants If Mainlining?

As topping the plant is stage one of this technique, this tutorial demonstrates that it is best to start the V-shape around the third internode. The reason for this is because you will need to work with the lower branches and the top two. When everything is tied down and spread out, the branches will all grow uniformly from the same starting position, so making sure you have 2 sets of main branches to work off is best. Growing Marijuana is about knowing when to remove branches and to remove tops.

Bigger Yields From Mainlining:

Using this technique will allow for a large central supporting stem, which looks like a letter X from above. As the plants grow back and focus their energy on the remaining growth, the stem will grow bigger and offer more support during the blooming phase. This technique is great for anyone who has problems with tall plants or is not growing plants with enough size and stature. Super cropping is incorporated with this style of growing so there are many variables that will ultimately lead to a higher yield. One main reason for the bigger harvest after this technique is used is that the plant will release many different hormones to aid it during recovery. By super cropping and tying down, the canopy will be flushed with growth regulators that will increase yield, size, potency and resin production.

A Form Of L.S.T.

This method of plant training is similar to L.S.T. in the sense that the top of the plants are facing downwards. This actually causes a reaction where the rest of the growth below the top shoot grows, allowing the plants to get a bushy thick canopy until the top of the shoot is back to facing vertically. There are also similarities between this technique and scrogging, as the lower parts of the plant are purposely removed to allow focus on the shape of the canopy. String or some type of twine is also needed to force the tops of the plants to face horizontally so this holds similarities to L.S.T.


Longer Growing Periods

As you will see in this video, there is a considerable amount of foliage removed from lower branches, new shoots and fan leaves. As the intention is to create an X-shape with the 4 main branches, the plant will require a longer growing period to recover not only from the low stress but also to allow the plant to produce the increased yields that are expected after the mainlining technique has been successfully used. Mainlining allows the grower to get really hands on with the plant as many styles of plant training are combined in this technique.