SCROG, netting marijuana intensive cultivation

The SCROG method, or Screen of Green, is an advanced cultivation technique that allows for maximizing the yield of cannabis plants in small spaces by using a screen or net. By using this screen or net, growers can control the growth of the branches and ensure an even distribution of light. The result? A more efficient crop, with more flowers and higher quality. If you want to learn all the theory behind optimizing every inch of your grow space, keep reading and discover the secrets of SCROG.

The philosophy of the SCROG growing technique is: fewer plants, bigger yields. Instead of growing tall, in SCROG the plants grow wide, colonizing the screen until they form a homogeneous green mass, thus optimizing the use of light, as each tip will be at the same distance from the light source.

How is a SCROG grow done?

SCROG is a very effective and easy-to-maintain technique, accessible to anyone, although it requires preparation, as it involves a lot of work at two key moments. The first is when you need to tie the branches to the screen, and the second is at harvest time.

How many plants are used in a SCROG setup?

Per square meter of growing space, you can use between 1 to 8 plants, although the ideal number of plants for a SCROG is 2 or 4 per square meter. The fewer plants you use, the longer it will take to cover the net, and you may waste light on areas without buds. Since you’re setting up the system, take full advantage by maximizing your harvest with the same resources.

For the recommended plant ratio, the final pots should be around 12 liters (in soil). If you use fewer plants, to maximize their development, you should use larger pots (25 liters or more for a single plant).

What screens should be used in a SCROG grow?

There are many options you can use, but the most recommended is a specific plastic screen for SCROG. You can also make one yourself with a framework of thin bamboo sticks (maximum 8mm in diameter), or other materials, but it takes time to make and isn’t worth it, as the price of ready-made screens is quite low.

Of course, if you have sticks of other woods instead of bamboo, they will work just as well. You can even make it using string or cord. What you shouldn’t use are metal nets (such as chicken wire or wire from some champagne bottles), as they heat up and can damage the plant. Whatever material you use, the screen or net should have holes between 5 to 20 cm.

How are plants positioned in a SCROG screen?

For a successful SCROG, the screen should be placed above the plants, about 20 to 40 cm above the pots. Placing it lower isn’t recommended because it will be harder to water and clean the pots, and the plant won’t have enough room to develop branches.

The two most typical ways of positioning plants are either at the edges (eccentric distribution), with the main branches parallel and the secondary branches perpendicular, or in the center (concentric), with the main branches toward the edges and the secondary ones arranged in a spiral.

Once the plant reaches the screen, we must place each branch in one of the holes, guiding it parallel to the screen underneath, and ensuring it covers as much of the surface as possible. This can be a bit tedious, as you need to monitor the plants daily as they grow to shape them and gradually occupy all the holes (for sativas, this can even continue until the second week of flowering).

It’s a daily and constant task; if a branch grows too much without being guided, you might damage it later when trying to bend it abruptly. As soon as a tip grows more than 8 cm above the screen, you should tuck it back through the next hole. Some growers prefer to tie each branch, but if you do this, avoid tight knots. Make loose ties, leaving plenty of slack, and use natural fibers that won’t harm the plant.

Once the plants stop stretching their branches, you can move on to the next phase, leaving the hard work behind for now. Now, it’s just a matter of letting the tips grow upward. If we’ve done it correctly, each hole in the screen should have a tip.

What type of pruning should be done in SCROG?

To achieve a perfect SCROG in cannabis cultivation, two prunings must be performed. The first is done throughout the plant’s growth stage, and the second in the pre-flowering phase.

In SCROG, topping during the vegetative phase is essential. Check out our article on apical pruning to learn more about this technique. Since we want our plants to branch out as much as possible, the first thing to cut is the central shoot when it reaches about 15 cm (minimum 3 nodes). This way, the plant’s hormones and energy are redistributed to the side branches, allowing them to develop further and grow horizontally, which is what we need to cover the screen as quickly as possible.

There’s also a special method for cutting the apical bud that results in double the shoots compared to a normal cut. It’s called FIM pruning (“fuck I missed”), which involves cutting almost all of the shoot but leaving 20%. This way, you can get up to four times more branches. In the links, you’ll see that we explain these two prunings together, as they are quite similar.

The second type of pruning, done when flowering begins, involves removing branches or leaves that remain below the screen and don’t receive light. This is done to focus all the plant’s energy on areas that get light, thereby maximizing results.

When does flowering begin in SCROG?

Indoors, we control the flowering cycle with light. During the vegetative phase, we provide a light cycle of 18/6. Then, once most of the screen is covered, we change the photoperiod to 12/12, and the cannabis will enter its flowering period. If you’re growing indicas, which stop growing earlier, the screen should be about 85% covered. For sativas, when the screen is 50% covered, it’s time to switch to flowering. This is because sativas continue to grow significantly even after they begin to flower, giving them more time to fully cover the net. It’s crucial to know the variety you’re working with to carry out a flawless SCROG.

The vegetative period will be approximately 5 to 7 weeks for indicas or when using fewer plants, and 3 to 5 weeks for sativas in the recommended proportions. Remember that the intensity of the light plays a decisive role in plant growth. If you’re unsure about the genetics of your seeds, treat them as if they were sativas. Otherwise, they may grow excessively and get too close to the lights.

What advantages does SCROG offer?

A major advantage of this cannabis growing technique is that it requires very few plants. One of the key benefits of this is that you don’t need to buy many seeds, allowing you to invest a bit more in the quality of the genetics you’re growing. Another big advantage is that with fewer plants, there are fewer pots to water, and overall maintenance is much easier. Finally, the greatest benefit of SCROG is the maximization of yield.

Thanks to the even distribution of the tops, the SCROG method is suitable for LED lighting, as it doesn’t require deep light penetration. Also, during the vegetative stage, you can use fluorescent lights or low-power lamps. Both options will help you save on your electricity bill.

The Screen of Green method is also used in outdoor cultivation to prevent plants from growing too tall, making them more discreet (especially if you live in a city), while also making better use of sunlight. Specifically, the advantages of the SCROG method are:

• Space optimization: It maximizes the use of the growing area, ideal for small tents or limited spaces.

• Improved light exposure: The plants grow through the screen, allowing each bud to receive direct light, improving yield.

• Increased yield: With more buds exposed directly to light, the plant produces more flowers.

• Control of vertical growth: Perfect for keeping plant height under control, avoiding issues with low ceilings or confined spaces.

Does SCROG have any disadvantages?

A few, but yes. Mainly, it requires daily work during the phase of filling the screen, and again during harvesting, as you won’t get huge buds like in a Sea of Green, but rather lots of medium-sized buds that will need to be cut and trimmed.

Necessary materials

• Screen or net: The screen is the essential component, and it can be made from various materials (plastic, metal, or rope). Buy SCROG screen here.

• Large pots: For SCROG, it is recommended to use larger pots, as the plants will develop more horizontally. Buy SCROG pots here.

• Guides to train the branches: Soft strings, wires, or clips to help guide the branches through the screen.

• Powerful lights: Light plays a key role in this type of grow. It’s crucial to use LED or HPS lights with good coverage to ensure the entire plant receives enough energy. Buy grow LEDs here.

Which cannabis strains are best for SCROG cultivation?

Sativas, without a doubt. For two main reasons: first, because these plants branch out a lot, allowing them to easily fill the screen, resulting in a good harvest with very few plants and in less time. If we used indicas, we would need more plants and would also have to spend more time in the vegetative phase to fill the screen. Secondly, sativa branches are quite flexible and can be easily adjusted to the screen without breaking.

Knowing that SCROG is perfect for well-branched sativas, all that’s left is for you to choose your favorite strain. We especially recommend Desfran, Silver Haze, 2046, Y Griega, Arjan’s Strawberry Haze, and Michka.

If you want to grow indicas, it’s probably better to go for a Sea of Green rather than a Screen of Green. You can also check out the differences between the two in this article about SCROG vs. SOG. Nonetheless, a large indica, like Sensi Star, could also work well.

It is essential to use only one cannabis strain in each SCROG grow. Mixing different plants will make it challenging to control their height and to provide them with the correct amounts of water, nutrients, and light.

We hope you enjoyed this content about the SCROG cultivation technique for cannabis. Follow us on social media and continue reading another super interesting article about how to fight mulch mosquito in cannabis.

Brais Nieto

Founder of Experiencia Natural, creative and entrepreneur, designer, master in grower and marketing. For a normalization of all plants and substances, giving priority to patients and users.