[franco.gh]

to satisfy many requests from growers I decided to give some extra info on the most debated subject of SCRoG


SCREEN OF GREEN


The SCRoG system is the practical application of a very simple concept: a screen, or net, is placed horizontally over the plants during vegetative growth, and the plants themselves are allowed to stretch through the screen towards the light. The height at which the screen is placed depends on many factors, including genetics, intended vegetative growth period, and desired crop height. The screen is usually made of nylon (even if hemp can be used as well) and it has open squares ranging from 10 up to 30 centimetres of size. The larger the openings the less support the plants will get. The way the screen is used varies according to the specific situation. Sometimes the branches are tightened to the screen to form a flat surface under the lights, while in other settings the screen has simply a support function for the vertically stretching branches and later for the buds. The benefits for the grower derive from the versatility of the system. On average SCRoG demands less plants per square meter compared to SoG, and it is actually very useful for a setup where very few large branchy plants are grown in a confined space.
When the SCRoG is applied in a grow-box context, it is usually to flatten the canopy and to form a solid, well supported layer of flowers, one that can be kept at the desired distance from the lamps without risk of overstretch and burning. When approaching SCRoG in a grow-box, it is important to consider a few determining factors: the heat threat, the absence of light under the screen, and the different needs in plant nutrition that this system requires.
The heat is always an issue in a grow-box system. The reality is that most producers of grow-box for the commercial market are more concerned with security and discretion than with plant health and well being. As a result, most grow-box systems lack proper ventilation in favour of a quiet and stealth setup. When the SCRoG is applied to a confined space, it is important to realise that there will be two completely different climate areas inside the grow-box: an “over-the-screen” climate and an “under-the-screen” climate. Over the screen the temperature will be much higher, and that’s where the hot air should be vigorously pumped out on a constant-flow basis. The fresh air should come from under the screen, travelling through the canopy to reach the exhaust fan.
Another issue to monitor is the almost absence of light under the screen. Because of this factor, it is recommended to trim any small branch and leaf that doesn’t receive enough light to stay green and healthy. By getting rid of these weak and penalized parts of the plants one will improve the general well being of the canopy, thus increasing production and reducing stress.
Finally, the different feeding needs of the plants have to be place into consideration: when growing long and stretchy side branches, plants can benefit from extra N and P during the first weeks of flowering (this being especially important when growing sativas). Moreover, longer branches and a hot canopy will demand extra water and at shorter intervals. The size of containers has to be large enough to allow plants to grow into and over the screen without penalizing growth pace.
SCRoG can also be successfully applied to very different situations, like growing really tall plants indoors. When vertical space is not an issue, maximal production is achieved by exploiting the height of the plants (again, this is particularly true when growing sativas).
In order to have very tall plants without the problem of falling branches during heavy cola formation, a single or multiple SCRoG can be applied. Multiple SCRoG means more than one layer of screen, where plants are allowed to grow through by being supported at different set heights. Usually 2 or 3 screens do the job, and they are placed between 30 and 60 centimetres from each other. The plants grow through the screens, and when they reach the top screen they are tightened to form a flat canopy. This system requires additional lateral light, as the stages of growth between the first and last screen have to receive adequate light to avoid stress and lack of productivity.
Once the screen is in place, and the plants are growing through, it should not be moved again. Therefore the growroom has to be built in a way that allows watering and maintenance without having to move or alter the screen position. If the screen covers a large area, automatic watering system is usually the best option, unless the plants are very tall and the screen is placed high enough to allow walking under it. As for the grow-box setup, it is convenient to trim the lower branches that cannot receive good light.
Overall SCRoG is not a system that can, or should, be seen as static. The only static factor in it is the position of the screen itself, but all other factors must be very flexible to guarantee best results. SCRoG should be seen as a way to improve an already tested growroom or grow-box. If, for example, one tries to grow really tall sativas but has falling branches and broken buds as a result, SCRoG is probably one of the possible solutions. Besides being cheap, easy to use and easy to dismantle, SCRoG is always a fun experiment. And at time of harvest the screen can be recycled to hang the plants for the drying process, in true expression of its flexible nature.

[skar]

nice reminding of the Scrog technique Franco.

i have a particular KillaQueen cut who stretch 3x even more..i used to top the plants and try to get 5/6 shots but even with that i still think she need a grow technique improvement and the Scrog could be the good one.

i might have to try this one day..maybe for the first grow after the summer...

thinkin' of 4 plants under 600w..big containers...

does topped plants do better under a screen or regular types are preferable ?

peace

[franco.gh]

I like to top the plants for SCRoG, the increased number of splits means less stretch and more horizontal bud surface.....
;-)

[SpacedCWBY]

I'm planning on revegging my two white rhinos and doing this. How well will they respond to a scrog setup?

[franco.gh]

WR can be scrogged with great success, especially with large-size plants.

If you reveg the WR I would then use the cuttings for the scrog. you will loose 4 weeks but it will be worth keeping the revegged plant as mother.

;-)

[tom&dan]

franco is the lemon skunk suitable for scroging, how does she react to scroging. thanks 4 any advice in advance.
Cheers Tom&Dan

[franco.gh]

you can scrog the lemon skunk but the long internode means the net should be a little lower than normal, to allow the branches to shoot through at least 20-30 cm before bending flat and tying to the screen....

[SpacedCWBY]

Originally Posted by franco.gh

I like to top the plants for SCRoG, the increased number of splits means less stretch and more horizontal bud surface.....
;-)

Would I still get those big long fat colas that the tops produce? Or just a whole bunch of smaller tops?

This top weighed almost 3/4 oz dried. How do the scrog'd tops do compared to this?



But I also got a lot of side branches that weren't nearly as big.

[franco.gh]

if you SCRoG the right way you can still get long colas, the trick is to place the net slightly lower than normal, and switch to 12/12 only after all shots have been tightened horizontally. This way the last stretch before flowering will shoot up straight, forming longer colas (depending on the genetics, of course.....)

Nice pics by the way..... enjoy!
;-)

[SpacedCWBY]

Thanks for the compliment. I enjoyed it. All gone now. Err... Too humid and stinky here to play in the garden so it's only a memory for now.

So what you're saying is don't let them get too thick in the net? Just let them veg for a short while and then switch them?

Thanks.