You have heard the term “stretch” used in regards to growing marijuana plants. But exactly is meant by this term? In this article, we will discuss how the term refers to plants stretching; what exactly that means, and how to manage it during your growing phases.
What the phase “stretching” refers to in the context of growing marijuana
The term stretch simply means a quick burst of growth in one or more directions. It also refers to growth that would be measured in length as opposed to an increase in overall circumference, bush or foliage growth.
How much do marijuana plants stretching during the vegetative stage?
As we’ve previously discussed, the vegetative period is the initial growing phase of the cannabis lifecycle. During this phase, the plant grows taller but does not bloom. And during this phase, your young immature plants can still stretch.
We typically see veg plants stretch in response to the height of the lights. If the lights are too far away, immature plants in veg can stretch to try to reach the light. This is generally considered a bit stressful, and therefore many growers will place their veg lights closer to the plant.
Because you use a low(er) powered light during Veg, there is no risk of burning the plant, as would happen with an HPS light used in flowering. So if you are using T5 fluorescent bulbs or other low watt LED, you can basically put that light right over the plant. As the plant grows, you can raise the light.
Don’t overcomplicate this or worry if you are doing it right. The only take home is that if you have a small plant, and the light is far away, you don’t want the little guy stressin’ itself out trying to reach the light. Help her out and place your veg lights closer to the plant. A couple feet above it works fine until the plant is several weeks deep into veg, and then you can move the light farther up.
How much do marijuana plants stretching during the flowering stage?
Now we are talking. This is where the phrase “stretching” really means something.
During the initial transition from veg to flower, your plant will go through what is called the Post-Vegetative Stretch. This occurs during the Weeks 1 through 3 of the flowering period. Basically, what happens is that your plant goes through puberty-like growth spurt during this transitional stage.
The excessive amount of light during the vegetative stage keeps the plant immature. But once the amount of light is reduced to the 12/12 light cycle, the plant goes through a tremendous growth spurt. This phenomenon occurs because of the increased recovery time afforded to the plants during the 12/12 flowering light schedule.
When your plant is subjected to 18 hours of light, and only six hours of darkness, your plant believes it is in the full summer season. It’s only objective is to grow, and so your plant does. But when you switch to 12 hours of light and 12 hours of darkness, you double the dark phase. This increase in the dark period triggers the plant into a puberty-like growth phase.
Your plant will essentially double or triple in height during the post-veg stretch.
How to Manage the stretching of your cannabis plants
How you manage the stretch will depend on what stage of life your marijuana plants are in.
During the vegetative stage, you can manage the stretch by topping your plant. This will halt the growth, and will increase the number of “tops,” or future flowering sites.
A practice that we use is to allow the plant to grow, from clone, for several weeks without topping. Then we will “top” or snip the center top. This will temporarily retard or delay the development of the center top. However, the other branches will be allowed to catch up, and will create what we call “the crown.” This is a great way to manage the stretching of once cola that far exceeds the height of the other branches or future cola sites.
Managing the post-vegetative stretch is quite another task, altogether.
The most effective tool you can use to manage the insane amount of stretch that occurs during the first three weeks of the flowering light schedule is trellis netting. Use the netting to capture the wandering branches and provide some sort of organization to what can otherwise become a hairy mess.
With trellis netting, you weave the branches through, and encourage them to grow outward, horizontally, as opposed to vertically and into your lights. The other advantaging of spreading them wide is you create more square feet of canopy, which will in turn produce more top cola flowering sites, and thus a greater yield.
Now, if you don’t mind growing a tall and skinny plant, then this notion of “stretching” may be of no concern to you. And that’s just fine. But if you want to maximize your yield, and prevent your plant from growing into the lights, follow the tips in this article. They have always seemed to work for us.