What is the ideal distance to grow cannabis plants?

By: Contributor Grow

You might be considering self-cultivating cannabis in an available space and you are wondering how many plants could fit there realistically. Making the best use of free space requires some experience, but there are some adjustments and techniques to maximise efficiency and to increase yields. So, as you imagine your grow room full of buds dancing before your very eyes, there’s a question you should ask yourself: “How far apart should I space my marijuana plants?”

One of the key factors when designing an indoor crop is determining the space between cannabis plants to achieve maximum production and to maintain optimal health. The main thing to avoid is overcrowding.

Your plants will branch out towards each other as they grow, trying to hog all the available light. When those branches start rubbing their leaves together, they become especially humid and lose their ability to transpire efficiently. This can spread mold among your plants, as well as thrips, red spiders and other pest problems, which can become especially dangerous when combined with insufficient temperature and humidity controls, as well as poor ventilation.

Overcrowding problems

Overcrowding can make plants face each other. Well, it’s not like they’re starting to betray each other or anything like ‘Game of Thrones’. Overcrowding plants have to fight for existing resources. And some of them will dominate and thrive, while others may not survive. Reducing overcrowding will reduce the chances of plants turning against each other.

Close-knit plants tend to stretch to get sufficient light and oxygen. As a result, some will end up growing more than they should. Their branches and stems will weaken and begin to lean on other plants, causing problems when you try to move them, including their branches breaking in half! Months and months of work could disappear in an instant.

In addition, overcrowding plantations tend to have poor air flow, so if you let the situation get out of control, you could end up suffocating your plants. You’ll know they’re suffocating if they gradually start to wither, dry out and then switch to that dreaded yellow hue that nobody wants.

How to properly distance your marijuana plants

Getting the right amount of plants (or, more importantly, buds) that fit perfectly in your grow space is determined by some factors:

Size of the grow room

Obviously, a decisive factor is the number of plants that can be fitted in a square meter. A large part of homegrowers tends to use grow tents, usually sized in meters. Depending on the technique and equipment used, an average of 1 to 16 plants can be grown in 1 square meter. If you want to grow only one plant, either with or without control, a single square metre is recommended. But if the focus is maximum efficiency and performance, and you only have 1 square metre available, then you can place more plants with the intention of training them or keeping them small when flowering early.


The cannabis strain you grow makes a big difference in the final size of a plant and will therefore affect how much you actually fit into that square meter. Some genetics accept training, while others need to expand if they want to produce decent yields. For example, indicas tend to grow short and bushy, unlike sativas, which tend to grow tall and branch out quite a bit. You can opt for genetically smaller plants (such autoflowering seeds), but the best approach is to consider growing a strain that produces plants about the same size and shape.

Lemon Haze Auto

If you are looking for an energizing and refreshing marijuana experience, Lemon Haze Auto is the perfect choice for you. With a high THC content (+18%), Lemon Haze Auto offers a very citric and refreshing taste. It is very easy to grow, making it suitable for beginners and experienced growers alike.


The size of the pots not only determines how many plants can fit in the growing space, but how big they can get. If you plan to place more than one plant, rectangular planting pots are recommended. Each pot needs some space around it, as the plants tend to be wider than the diameter of their pot. To get a rough idea of the size of the pot in relation to the number of plants that fit in a 1×1 metre space, you can play around with the 25 plants that would fit 3 litre pots (or 18 in 5 litre pots) and the 2 plants you should plant in 18-litre pots (or a single plant if it is a 21-litre pot).


The more grow light intensity, the more light is distributed throughout the space. A higher output light covers a larger area, meaning more plants can be grown. Depending on the lighting design, the edges of the square metre may not receive the same amount of light as the centre. That means that the light must be powerful enough so you can place it at the right height and each plant gets a fair share of the light resources. For example, a minimum of 400 watts power bulb is recommended for a space of 1×1 metres, but with a 1,000 watts spotlight a space of 1.5 X 1.5 metres could be covered.

Air flow and ventilation

For each 1,000 watt bulb, there should also be at least one oscillating fan to increase the air flow through the room space. You should see a slight breeze moving the leaves and branches from the tip to the base. If there are some specimens trapped in a stagnant air zone, you should distance your marijuana plants further. Still air can damage them when the leaves are too moist.

Training techniques

Growers looking to maximise yields in a small space often choose to train their plants, which determines the efficiency with which they use the available space. There are multiple techniques, but the best known are:

  • Sea of Green (SOG): this method consists of growing many small plants in small pots. (4-16 plants/m2)
  • Low stress training (LST): plants can be manipulated by bending and tying down branches to achieve the desired shape. (1-4 plants/m2)
  • Screen of Green (SCROG): consists of placing a grid-like mesh on the plants, which allows controlling the height and even the canopy. (1-4 plants/m2)
  • Topping/ Fimming: both are high stress training techniques involving breaking the apical dominance to limit height and boosts yields. (2-9 plants/m2)
  • Mainlining: involves intense manipulation of branches and leaves to keep them very low, but allows them to develop large cluster of buds or colas. (1-4 plants/m2)

What is the ideal distance to space your plants?

You should therefore play with all these factors when considering how far to distance your weed plants. Keep in mind that when you are distancing plants, the ideal is at least a 15 cm to 30 cm of room between the branches. The distance will vary, but this reference gives a good margin to maneuver as you care for your little friends. You can space the plants closer, as long as they do not touch, but at least 15 cm is a good rule of thumb.

And remember that there is no really exact equation about how far apart weed plants should be in a grow room. Each plant has a different shape, each variety has its own needs and each room has its own dimensions. However, making sure the plants are far enough apart so that they don’t touch is the starting point when it comes to home growing indoors with guarantees of success.

Kannabia Seeds Company sells to its customers a product collection, a souvenir. We cannot and we shall not give growing advice since our product is not intended for this purpose.

Kannabia accept no responsibility for any illegal use made by third parties of information published. The cultivation of cannabis for personal consumption is an activity subject to legal restrictions that vary from state to state. We recommend consultation of the legislation in force in your country of residence to avoid participation in any illegal activity.