Growing marijuana with the ‘Screen of Green’ SCOG method
What is Screen of Green?
Screen of Green, or SCROG, is one of the most productive systems for growing weed that there is. Cannabis plants are trained through a horizontal screen placed above them, spreading the tops of the plants along a horizontal plane and encouraging bud formation along the normally neglected branch stems.
Growing marijuana in a canopy, as with Sea of Green (SOG) methods, makes the most efficient use of light, in a SCROG grow however, unlike Sea of Green, the vertical growth of the cannabis plant is limited, forcing its energy out laterally along the screen. A SCROG grow is particularly suitable for small stealth grows. It will make the best use of smaller lights and can work very well with both LED grow lights and reasonably well with compact fluorescent CFL grow lights despite some online sources stating the opposite.
When using HID lights that produce lots of heat like HPS lights the most productive area is in a flat circle just beneath the bulb. For example, with a 250W HPS the most productive area is a horizontal circle about 20” (50cm) below the bulb. A 70W HPS has a productive zone about 8” (20cm) from the bulb and with a compact fluorescent CFL grow lights and LED grow lights it is about as close to the bulb as you can get within reason.
With the Sea Of Green method the cannabis plants in the canopy form spikes, creating a forest rather than a field. This means that only the plant tips are in the most productive area of light. By keeping the canopy flat in a SCROG grow, all of the buds are in the productive zone. Your cannabis plant loves this and will reward you with many buds, all growing upwards from the screen as small kolas.
Why Choose Screen of Green way to Grow Weed?
- SCROG is suitable if you are limited by vertical space and as such is ideal for stealth grows in cabinets, old fridges, purpose built grow tents, containers and other restricted spaces
- SCROG uses light in a very efficient way meaning more yield per watt, or more buds for your buck
- Growing marijuana with the SCROG method is just plain fun. It is hugely rewarding and through it you will develop a better understanding of how cannabis plants grow
- Be aware that this method means more plans and that might cross the law when compared to just growing a couple
How to Grow Cannabis Using the Screen of Green Method
The defining part of a SCROG grow is the screen. Poultry netting, garden netting or even a hand tied grid are all suitable. Be sure that the screen is fairly sturdy, your burgeoning crop will put some strain on it.
The holes need to be around 2″ (5cm) square. The size of the screen will obviously depend on how many plants you are going to grow through it. It is possible to grow just one marijuana plant with a SCROG, or if you want to grow more it is only the availability of lateral space that limits you. Many large scale operations with upwards of a hundred plants per time are grown using the SCROG method.
The size of the screen also depends on how long you are going to let your plants veg before putting them on to 12/12 light. It is possible to treat a SCROG like a Sea of Green grow and put the cannabis plants onto 12/12 early, making for a quick crop especially if you have the right strains. If you have space and time however you can use a large screen and allow your plants to fill it, producing a bumper harvest but taking longer in the vegging stage. It’s up to you to decide how you want to do it. Most people will go for somewhere in the middle.
Fit the screen about 8” – 12” (20cm – 30cm) above the pots or growing medium. This should allow enough space to get your hands underneath to work and to enable the plants to branch. Branching is crucial to the SCROG process.
As the plant tops grow up through the screen use your fingers to tuck them back underneath it, training them so that they grow outwards across the screen. Try to direct the tops towards the empty spaces in the screen. Remember, the ultimate aim is to fill it completely.
As the screen fills and a canopy develops the space beneath the canopy becomes shaded and can be susceptible to mould. Trim back all growth beneath the canopy. Don’t hold back here. Any growth beneath the canopy will draw energy away from the bud sites and obstruct ventilation. If you have some smaller lights like LEDs you can direct them to the side and help keep mould to a minimum.
Good ventilation beneath the canopy is crucial to avoiding mould problems, ensure a constant flow of air here. If you are using HPS or MH grow lights you will need to make sure that all this vegetation has good access to fresh air whilst you exhaust the hot air. The better broad spectrum LED grow lights are far more energy efficient and turn electricity into light with about 5 to 6 times less heat production than an HPS or MH lights.
When to Induce Flowering with the SCROG method
Deciding on the right time to put your marijuana plants on to 12/12 lighting will depend on various factors. Apart from how much of a rush you are in, the most important factor is the strain that you are growing. Cannabis strains that are known to stretch will need more room to flower. A good guide as to when to induce flowering is when somewhere between 40% and 60% of the screen is covered with leaves.
What cannabis strains are good for the SCROG method?
Get to know the characteristics of your cannabis strain. Ask other people who have grown the same strain, we would suggest going with some dwarf strains such as Buddha White Dwarf Auto-flowering feminized or Lowryder 2 Auto-flowering feminized. If the cannabis strain you are growing is known to stretch then start it earlier than you would if you have a more compact, slower growing strain. If you have time a robust sativa will reward the good gardener with some excellent yields. We would particularly recommend a quality sativa like Durban Poison and, if you have the space, Super Lemon Haze.