Before you get your grow on, you need to have a plan and a timetable. First, you need to establish the size of the available grow space. Grow tents come with exact dimensions on the box. However, if you are building your own grow box, or converting a whole room into a grow-op, you need to first take measurements. Next, you must decide how much light you can put down while still maintaining optimal environmental conditions. We will breakdown the key factors to consider when choosing grow lights a little later.

How Many Plants Per Square Meter Cannabis Cultivation

Perhaps the most important question the grower needs to ask him/herself is; how much time can I commit to cannabis cultivation? Work, family, and social commitments can make growing a difficult balancing act. A large sativa plantation will be far more time-consuming to maintain than a couple of autoflowering plants  in a wardrobe.

The genetics you choose and your preferred grow style will ultimately determine how long it takes to bring your crop to harvest. Precisely how many plants to grow is a personal choice. But the following will help you discover your indoor marijuana magic number.

Plants By Square Meter Cannabis


It’s not as simple as purchasing as many of the most powerful grow lamps you can get your hands on. Every grow space is different. But two factors always need to be tightly controlled and constantly monitored. Temperature and relative humidity (RH) are the key environmental conditions the indoor grower regulates. You need the right tools. Invest in intake fans, extractor fans, and if available, air-con or heating.


HID lamps are a great source of illumination for the grow room and still favoured by most professionals. Unfortunately, MH and HPS lamps run hot and will significantly increase your power bills, too. One 400-600W bulb per m² is a good rule of thumb. Although, you may need to scale down to a 250W bulb. Consider improving side reflection with Mylar sheeting if you can’t keep temperature and RH dialled-in. Using high-powered old-school lighting necessitates the use of more powerful fans and possibly air-con, or else the grow-op may run too hot.


Modern LED grow lights run much cooler and more efficiently than HID. The main drawback with next-gen LED is the substantial investment required for a decent high-quality kit. Over the long-term, you can recoup with the savings you make on the power bill. Choose your LED kit carefully as not all LED’s are created equal. At present, 3W diodes and COB appear to be the most promising technologies. Less heat and more usable light per watt can also save you some money when it comes to selecting fans to regulate airflow.


CFL can only take you so far. Sure, they are economic and efficient, but only to a point. In this writer’s opinion, cool white CFL is fine for vegetative growth and rooting clones, but nothing more. Using CFL’s alone for the bloom phase is not recommended. However, adding CFL as a supplement to HPS during bloom can be a winning combination.


The sea of green method (as the name implies) is all about packing all of the available floor space in the grow-op with plants. Typically, photoperiod clones or autoflowering strains are used to achieve a consistent, controlled outcome. This technique is fast and very high-yielding. Rooted cuttings get from 1-2 weeks of vegetative growth before the switch to standard 12/12 flowering of 8-10 weeks. On the other hand, autos can be kept on a consistent 18/6, 20/4, or 24/0 schedule and be ready for harvest in 8-10 weeks from seed. There is no time for pruning or training, nor is it needed.

As plants are not given time to branch out, many short plants with chunky main colas are the objective. Approximately 4-16 plants per m² can be cultivated under 400W HPS, sown in 5-12l containers. Watering by hand can be very time-consuming with such large numbers. Many growers prefer hydroponics kits with automated feeding systems when cultivating many plants. A well-run SOG grow-op can deliver 4-6 500g/m² harvests per year.

Main Lining Cannabis


If you want to keep the number of cannabis plants to a minimum and still get maximum yield from your grow space, then you need to apply yield-boosting techniques. You have two choices; pruning and training. Of course, you can do both. In fact, we highly recommend combining methods for best results.


The most common pruning-for-yield methods are topping and fimming. By pruning the main stem and breaking the apical dominance, bigger yields can be achieved. This is done either with a clean cut by “topping,” or a pinch leaving 25% of the main tip via the “fimming” method. Plants will bush out and develop multiple main colas instead of just one. Both methods can be applied repeatedly depending on how much lateral space you wish to fill.

Remember, each time you prune marijuana, you must allow recovery time. The cost of these pruning-for-yield methods is indeed time itself. Expect an extended vegetative growth cycle. 6-8 weeks will be required for two well-pruned bushes to fill out 1m².

Topping And Fimming Cannabis Growing


LST or low stress training is a beginner-friendly training technique that, like the two aforementioned pruning methods, works well with a ScrOG or screen of green technique. By bending or tying stems during vegetative growth, the grower can manipulate the plant to grow more like a bush. 2-4 plants can effectively fill 1m². Recovery time is just a few days and this method even works with autoflowering strains.


If you consider yourself to be an experienced grower, having mastered the other techniques we've mentioned, you can optimise your yield further by bringing “screen of green” into the picture. But what is a ScrOG, exactly? Basically, it's a grid-like screen made of chicken wire (or similar mesh material) through which the shoots of developing cannabis plants are woven to control growth. You'll want to start this weaving process during the vegetative phase, ending it before the third week of bloom. This keeps exclusively the main colas under the light, focusing the plants' efforts on bud production. You'll also want to top your plants early so their branches grow as long as possible, then proceed to train them in multiple directions through the screen. As a result, you can utilise the full surface area of your growing space.

As far as spacing is concerned, if you're growing one plant per square metre, you'll want to use 20I pots at least. Those who want to cut down on harvest time, however, can fit four plants, each in a 10I pot, in the same square metre. There's no strict rule with these limits. However, we've found that sticking within these general parameters is the safest approach.

Scrog Screen Of Green Cultivation Technique Cannabis

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