SCROG technique for growing cannabis
The SCROG technique (Screen of Green) is one of the methods used in cannabis farming to ensure optimal yields easily and without much trouble. In contrast to the SOG technique (Sea of Green) that we already know, in a SCROG grow much less plants per square meter are used, which of course have pros and cons.
Indeed, a number of 25-36 relatively small plants (5×5, 6×6…) would be used per m2with the SOG technique, so plants don’t need a prolonged vegetative period to be ready to bloom and we can switch to flowering around 15 days after seed germination. If we don’ t have a small veg room to grow our plants while the current grow ends, this method allows a quick transition between crops. It is then ideal for plants of average size and automatic cannabis strains.
On the contrary, we need few plants per m2 with the SCROG technique, which must be bigger (more branched) than those used in a SOG grow. At first glance, the SCROG method has two main advantages: on one hand, we need much less plants to cover the same surface, so costs in seeds or clones are considerably reduced. Furthermore, any grower knows that it is easier to take care of 4 plants than 25 or more, regardless their size. On the other hand, another advantage of this tech is related to legal aspects. While in most countries there is not a legal number of plants, for a judge it is not the same to read a police report where 4 plants are mentioned than dealing with someone with tens of plants.
The main disadvantage of the SCROG system is the long vegetative period needed for the plants in order to reach the needed size and number of branches. Plants grown with the SCROG tech need several weeks of growth prior to bloom to fully cover the growing space, which can be a drawback for intensive farmers who don’t have another room for growing their plants. Another disadvantage is the fact that autoflowering strains can not be used, since they would not grow enough before automatically start to bloom. Let’s see know what is exactly the SCROG technique.
Cannabis and the SCROG technique
As we already know, we need few plants for this type of grow since what we want are well-branched plants which can cover the entire surface dedicated to our grow. Some growers use 9 plants per m2 (3×3), although only one plant can be used, you only have to grow it big enough before switching to bloom. We’ll use an example with 4 Easy Haze plants, which are perfectly suited to this technique due their awesome vegetative vigor.
As our plants will end the flowering stage with considerable size, it is always better to use large containers. Depending on the growing medium chosen we can use 7-11 litre pots (for coco coir) or 15L containers (for conventional organic soils). It is worth mentioning that many growers who use this technique have hydroponic/aeroponic systems in order to reduce at most the growth period of the plants.
Once everything is ready in our indoor grow room we can set the photoperiod to 18/6 and start growing our small seedlings or cuttings. When our plants develop the 4th or 5th node we can prune the tops of the plants to get a more branched structure, promoting lateral growth. As the plants grow we’ll prune their tops to get bushy plants with lots of branches and without a defined prominent main stem.
When our plants reach 50-60cm in height it is time to put a screen or mesh above their tops covering the whole growing space. This mesh must have holes of around 10x10cm so the tops of the branches can be easily passed through them. In this way, we can cover each hole of the mesh with one top, thus creating a uniform canopy that will turn into a beautiful garden full of colas once in bloom. The mesh also supports each branch, so no plant tutors are needed during the flowering stage. The time needed to cover the entire mesh depends on several factors, as happens usually when growing cannabis indoors: environmental conditions, available light, growing system, genetics, etc. If needed, the mesh can be raised as plants grow in height.
Once all the holes of the mesh are covered we can switch the photoperiod (12/12) and thus start the flowering period. Plants will stretch considerably during the first 2 weeks into bloom before developing the first buds. Once this first stage is finished, remove all lower branches below the mesh so plants focus their energy on developing huge top colas. We only have to wait until harvest to enjoy the fruits of our efforts.
As we mentioned before, the SCROG technique is ideal for seeds or clones of vigorous strains. The more vigorous the growth, the less time it will take to cover the growing space and start the bloom period, thus reducing the time between harvests. Mostly Sativa strains are perfect for this tech, as the aforementioned Easy Haze or Amnesika 2.0, Fruity Jack or Spicy CBD. Also our new strain Jamaican Blueberry BX, which has inaugurated Philosopher Seeds Regular Line.
If different strains are to be used in the same space, we recommend to choose plants with similar growth pattern and flowering period, otherwise it can turn into a very difficult grow. Keep in mind that this technique is also suitable for outdoor growers, being ideal to grow large plants with lots of branches but relatively short height and to hide them behind walls or fences.
We hope this post will encourage you to try this interesting cultivation technique. We’ll be pleased to reply any doubt or comment.
Best of luck!
- 27 December 2016
- Marijuana Grower's Handbook