Part 2, Vegetative Growth & Plant Contortion

Marijuana cultivationEnvision the Result, like Mr. Miyagi…

As a gardener gains the experience of seeing many crops grown to completion, they develop a perspective that, after time, allows them to anticipate what a plant will become once finished, based upon its genotype and structure, even when in the early in the vegetative stage.  This allows for precise control of the flowering canopy structure, well before the plants reach flower.  Encouraging the gardeners to take notes on each batch, to take a detailed visual assessment of each completed batch before harvest, and perhaps even a photo to jog the memory, is recommended.  Seeing the result of a crop or batch, viewing the related data, and making adjustments which will in theory improve the previous result, is the best method of increasing canopy output and efficiencies.

Sharing accurate yield data is crucial, as the proof is in the pudding, and that information should drive the decisions made regarding gardening technique and logistics.  I recommend a full-time employee just to assemble the data from the garden, yield obviously, but also all related costs to allow finding other efficiencies.  If the garden is large, and the vegetative and flowering growth is managed separately by different departments, there should be strong communication and the cause and end result of the vegetative team’s effectiveness of plant contortion and pruning should be studied and constantly improved.

The three dimensional structure of the flowering canopy consists of square footage and depth.  If growing medium size plants, the bud sites can be productive several feet into the canopy.  As always, the nuances of specific genetics make varying results, as certain examples will grow taller, with better light penetration through the canopy due to skinny sativa dominant leaves, or may happen to be able to generate worthwhile flowers in a limited light condition.

Topping or pruning is the practice of removing the tip of a branch to encourage lower growth and to inhibit a plant from stretching and to create more primary nodes which will add additional flower sites by allowing the lower branches to catch up in vertical growth, closer to the light.  Although often abused, this is the most common example of contorting a plant for optimal yield.

Like all plant contortion techniques, it is inevitably plant count and strain specific.  Many genetics will grow straight up vertically, with an overly large central cola, creating the likelihood of bud mold and reduced yields due to a limited amount of bud sites positioned close enough to the light. If executed at the right time, to the correct degree, and with adequate lighting, topping a plant once or twice is usually all that’s required.  Once a cutting has been propagated for a few weeks and is beginning aggressive vertical growth, it is recommended that it receive its initial topping, which forces the lower branches to catch up vertically with the central primary node before the plant has grown large, making it the most efficient time to do so.  This typically results in three or four primary nodes, which may or may not be adequate, depending upon the example’s growth structure and plant density per square foot.  When more nodes are required, it is recommended to top in the vegetative stage once more, doubling them from six to eight.

Topping is additionally effective when the flower room is full and plants need to held in the vegetative stage longer than necessary.  Although this may cause smaller top flowers and more branches to manage than necessary to achieve the desired yield from the upper canopy, without cutting them back, they may become unruly, starched specimens that are unsuitable for maximum output.  If done correctly during vegetative growth, topping won’t be necessary once the plants are flowered.

Knuckling, or bending plants, is supplemental method to achieve a plant structural contortion that’s ideal for maximum flower output.  Freshly grown branch plant material is rather pliable, allowing a gardener to gently bend the stalks in the opposite direction requiring it to work to correct itself and allow lower branch to catch up vertically allowing for superior exposure to the light.  Additionally, one can “knuckle” the branch by making an aggressive bend that creates a 90 degree near break in a branch that then will heal and drastically reduce that branch’s vertical growth, maintaining its node sites rather than removing the branches.  It’s usually used for damage control once things are getting out of hand vertically in flower.

The best practice for limiting unwanted vertical growth after minimal topping is to utilize high PAR, or light intensity, to force the plant’s upper branches to not reach toward the light, as they are saturated already.  Sometimes, with a durable, vigorous genetic in the vegetative stage, one can use this method to point of nearly during the top plant material from light intensity (don’t start a fire!) which will result in the plant being forced to focus growth on thicker, stronger branches and increased vertical height on the lower branches, while still allowing for the stresses plant material close to the light to heal with no consequence once in flower.  This is extremely effective in allowing shorter plants within a batch to catch up with the rest for an even canopy as well.  While some lights now are equipped with a dimming capability, the other option is to manually adjust the height of your light to the desired distance above the plants.  Although PAR meters aren’t at all necessary to accomplish this, they can be a useful tool to dial in exact light intensity and study nuances across the garden.

Although it is best to use the lower canopy to maximize yield, inevitably there will be some branches exposed to limited light, or so weak, that they are unusable for any worthwhile flower production, and these will be removed, as they are a waste of the plant’s energy and susceptible to pests and disease.  The technique of “lollipopping,” is the practice of removing lower branches with the purpose of focusing more of the plants energy to the higher, more productive nodes.  While this is effective, gardeners should be conscious the balance required, allowing the useful branches to remain, while removing the rest.  Often, gardeners get to aggressive, and underestimate the potential output of the lower branches.  I should be noted that the amount of lower branches that are useful will be strain specific, as some genetics have wider leaves, affecting light penetration through the canopy, and specific genetics possess varying abilities to have useful flower production in lower light conditions at the bottom of the canopy.

As has been noted, a specific genetic example’s growth pattern and structure will dictate how each should be contorted, as individual plants and within canopy as a whole.  While we can discuss in the generalities of Indica and Sativa, it’s important note that these are always exceptions, and each genetic should be used by the all the factors that affect the optimal way to construct a canopy: growth pattern, plant density, ability to flower on low lit branches, how explosive the initial vertical growth is in flower, etc.  All plants are essentially hybrids to some degree at this point, as there has been so much cross breeding with cannabis, that it has all become shades of grey.

It is well know that Indica dominant strains tend to grow wider leaves, have closer internal distance, and are shorter in height.   Sativa dominant examples are assumed to have skinny leaves, to grow taller/bigger, and have such an explosive early flower growth rate that they might double or triple in size, and require aggressive training to prevent them from becoming unruly.  Due to these generalized differences, that the two extremes require different treatment as they have very different grown patterns in vegetative and flowering.  Proper plant contortion and training in the vegetative stage will effectively prepare a high output flower canopy, which is imperative to achieving maximum yield potential, which is the acute factor in the bottom line of a garden’s profitability.

-Part 3 will review flower canopy management

By Ben Burkhardt