micro grows cannabis

What Is Micro Growing Cannabis?

Growing your own cannabis has been gaining a lot of popularity, people who can’t find good quality flowers or don’t want to deal with dealers are starting to grow their own. Even though it may seem super hard and expensive, having your own growing space doesn’t need to be hard at all, you can grow like a pro indoor, even in smaller spaces.

A micro cannabis grow consists of scaling down a grow tent, the only difference being the amount of space available. This results in a fully functioning indoor growing space that can fit in a small closet, a homemade grow box or even smaller spaces like a computer case or a cupboard.

1. Cannabis growing conditions

Just like in all other growing setups, you will have to provide a good environment for your plants to grow, this can be a bit hard when dealing with small spaces but it’s not impossible.

For your plants to grow properly, you will need to provide and maintain a relative humidity in between 60-50%, a temperature ranging from 18-25°C and 18hs of light for autos and photos in the vegetative stage, and 12/12 for photoperiodic strains in the flowering stage.

Despite being smaller, the growing space needs to have everything a normal-sized growing space has, so you won’t need to spend too much but you will need the basics.


There isn’t a big difference when growing in a small space, obviously you’re limited by the space you have available so you’ll have to choose the genetics wisely and perform plant training but other than that, it’s basically the same.

The challenge when micro growing cannabis is to be able to provide and maintain a good growing environment for your plants, this can be difficult when growing in small spaces but it’s not impossible, you most likely won’t get it right the first time but after making minor adjustments it will work like a charm.

3. Main requirements

Providing the needed amount of all these elements is crucial if you want to have a successful harvest, you will not need to spend too much or buy super expensive equipment but remember that when growing indoors you are responsible for controlling the environment your plant grows in so these things are obligatory.

Micro growing setups are usually homemade, it doesn’t really matter the material or size of the grow box as long as you provide everything your plant needs and that is:


Light is a key element in plant growth, obviously you won’t need a high-intensity light fixture but you will need to provide the appropriate amount of light for your plants to develop.

You cannot grow cannabis without light, that’s a fact. It doesn’t matter what kind of light you use either an LED or light bulb, now, light bulbs emit heat but can be near the plants while LEDs don’t emit much heat but can bleach your plants if they’re too close to the plants so depending on the growing space you will have to choose one or another.

Because of the limited space, you won’t have a lot of plants so you can also use fluorescent tubes and CFLs but remember to provide at least 400w per m 2 and have in mind that when using light bulbs you have to use white lights in the vegetative stage and yellow lights, almost all LEDs are full-spectrum so you won’t need to worry about this if using LED fixtures.

It’s essential you provide a wide light spectrum if you want to get dense buds so make sure you take extra caution before buying the lights.

Ventilation and Air exchange

Like said above, plants need CO2 to perform photosynthesis. There are around 400PPM of carbon dioxide in the air we breathe so there’s no need to provide more than what’s already available but you will need a way to exchange air.

Because the space is limited and you don’t need and can’t fit an exhaust fan, you can achieve this just by having the door open or a couple of holes for the air to naturally circulate, this way you avoid having problems.

If you don’t make sure the air is exchanged several times a day, your plants will not be able to grow properly because they need CO2 to perform photosynthesis.

You will also need a small fan to help the air circulate, this will not only help exchange air but will also prevent bugs and make your plant’s branches and stem stronger.


Plants need macro and micronutrients to grow properly, if the medium is sterile and you don’t feed your plants, they will start to show nutrient deficiencies and can stop growing at all.

Because the pots are usually smaller and contain a smaller amount of soil (or the medium of your choice) you will have to water more often and maybe divide the nutrient dose you would give once in two or three, this will help your plant absorb it easier because the medium can only hold a limited amount of water.

Have in mind that you can grow photoperiodic strains but you can have trouble controlling their height so if you’re a beginner grower it’s better to start with autoflowering plants so you don’t risk ending up without a harvest.

Appropriate pot size

As you may know, the size of a plant is a reflection of the size of the roots so using smaller pots is necessary in smaller growing spaces, because the pot is smaller and will have less medium, you will have to water and feed more frequently.

Even though the size can vary from strain to strain, here’s a chart to help you have an idea of the approximate plant size for smaller pots:

Pot size Plant height
1/2 L 20cm
1L 35-40cm
2L 45-65cm

This will also keep the branches shorter but depending on the strain, your plant can develop a lot of branches that you will have to control with plant training techniques if needed.

4. Choosing the strain

Because of the limited space, you will have to choose the right genetics so you don’t have a problem further into your plants growth cycle.

In this type of setup autoflowering strains are ideal, although some strains grow taller than others, so you have to be careful and pay attention to the information the breeders give.

For example, if your growing space is tall and narrow you’ll be better with Sativa-dominant strains, Sativas grow tall and skinny and are better for this kind of grow space whereas Indica-dominant plants grow short and bushy and are better suited for shorter and relatively wide.

5. Plant training

When growing cannabis in a limited space, plant training is essential. There are a lot of plant training techniques that not only allow you to control the size your plant will have and even out the canopy but also help improve yields.

In small growing spaces there are a couple of growing techniques that are recommended:

Tying down branches

The tie-down method is fairly easy but you won’t be able to grow more than 2-3 plants in a limited space, this is because tying down the branches allows you to control the height by training your plant to grow to the sides.

You can also use high stress training techniques like topping or fimming but to effectively perform these techniques you need a bit of experience, HST techniques are not recommended with autoflowering strains but can be used with photoperiodic cannabis so you have to know what you’re doing so you don’t risk your harvest.

By choosing the better-suited strain for the space you have available you won’t have a problem, and if it grows a little bit more than what you expected, you can use any plan training technique you find appropriate.


Screen of green (aka Scrog ) consists of having a trellis net on top of your plants, this will not only allow you to control height but will also open up the branches so your plants have more airflow in the buds and also allows the light to reach deeper.


A sea of green (aka Sog ) is the most appropriate technique for this type of cannabis grow, it consists of having a lot of plants, growing small and not producing too much individually but will add up to a lot after harvesting all of them.

The plant training method you use will depend on the space you have, remember you don’t have to use just one, you can combine (for example) the Scrog method with the tie-down method to reach the desired height and structure.

6. In conclusion

You can grow cannabis in any space as long as you provide the basic elements a plant needs, it doesn’t matter if it’s a huge or a tiny growing space.

If you have experience with this type of growing, please feel free to share your tips and tricks in the comment section below!

Even in a smaller space, you can grow like a pro. Micro growing is for those who want to grow good buds stealthy and in a small discreet growing space.

What You Need To Know About Cannabis Micro-Growing

Published : Feb 16, 2018
Categories : Cannabis cultivation

Micro-growing is the optimal solution for growers with limited space and resources to facilitate a successful cannabis grow. By optimising several necessary variables, you can crop impressive buds in spaces as small as a cabinet.

As cannabis is moving more and more into the mainstream domain, more and more novice cultivators are looking into cropping their own cannabis plants. Few individuals have the large space requirements and breadth of knowledge to set up a full-sized grow. “Micro” means small, and micro-growing involves cultivating few cannabis plants in environments with major spatial and resource limitations. The process of micro-growing is perfect for new growers looking to experiment with home cultivation, without wasting money and time on a crop that may never come to fruition. In short, micro-growing is the predominant way growers find out if the process is right for them.

Because micro-grow operations are usually conducted in very small spaces – think closets and tiny spare rooms – it is very important to cultivate with the goal of keeping things as simple and compact as possible. This, of course, is easier said than done. With this guide, however, we hope to provide general tips on maximising the variables that go into micro-growing.


Lighting is a crucial element in any cannabis grow, and there is a lot of debate surrounding which lights are most ideal for each kind of operation. The most potent lighting system is the obvious choice, but it isn’t ideal in all cases. For a micro-grow, excess heat and light too close to the canopy can seriously damage your plants. It just so happens that the most powerful lighting systems also usually produce a lot of heat.
While some of this heat can be mitigated with proper cooling and venting practices, this also has its limitations. As a result, micro-growers are largely limited in what they can use. Here’s a breakdown of the most popular lighting systems.

• HPS: HPS lamps, which are a tried and tested staple in indoor grow environments, tend to produce a lot of heat. For this same reason, we do not recommend using an HPS lamp that is stronger than 250 watts in an area that is 1.5 metres or lower. It will simply generate too much heat, leading to heat stress and an amalgam of other potential issues. If the potency of a 250W bulb doesn’t let your plant flourish, it is possible to combine or supplement with LED or CFLs, which do not generate as much heat.

• CFL: These fluorescent tubes, as we have all seen in offices, generate very little heat. At the same time, they are far less potent than HPS bulbs and can be placed closer to the canopy without overheating the plants. Also, they are fairly affordable. However, CFLs are primarily used during the vegetative stage, as you would need several lamps to accommodate the changing requirements of your flowering plants. A more blue light spectrum is desired during vegetation, while a red light spectrum is more advantageous during bloom.

• LED: LED lighting is becoming better and more popular every year, and is a very suitable solution to our heating problem. It has a wide light spectrum, able to generate all the colours HPS and CFL can, but it generates very little heat in the process. LED lighting does come with an issue, however; it can be quite expensive outright. This might not be the solution if you are looking to build your cannabis growing space on a tight budget.


Airflow is important to all cannabis cultivators, but especially so for micro-growers. One of the best ways to achieve healthy air circulation in very small grow-ops is to use computer fans. These are small and silent, and easy to set up.

Place an exhaust fan near the top of your grow space, and leave an opening in the lower end. The hot air generated by the lights will rise and be ejected by the exhaust fan. This allows new, fresh, cool, and CO₂-rich air to flow in. For extra cooling, install an intake fan at the bottom of your space to make the process more streamlined. For stealth grows, it’s usually important to install a carbon filter, which neutralises the odours formed during the bloom phase.

Depending on the relative humidity of your micro-grow space, your plants may require more watering than they would regularly. Although you should still take care not to overwater, don’t be surprised if your plant’s need for moisture is elevated. Given that most micro-growers crop indica or indica-dominant hybrids, the plants will likely become bushy and compact. Make sure you are able to easily water your plants by pruning or training as necessary. More on that later.

Your choice of soil is also quite important. It should be rich and drain well. Anything with a muddy or clay texture is a no-go. One consideration, especially for smaller operations, is the actual amount of soil used. Large containers will obviously take up too much space and may make it harder to light your plants. At the same time, tiny containers will stunt growth and make your plants rootbound. When looking to achieve “normal height” plants, you’ll want a 12l container. If you want to contain growth, 5l will limit height to around 60cm while 2-3l will allow the plant to only reach 24cm. It’s all about your exact limitations, strain, etc. Square containers take up less space than round pots. Low and broad containers are often a good fit for most indoor micro-grow environments.


It might not come as a surprise that not every strain is equally suited to be grown in small spaces. Most sativa or sativa-dominant strains simply grow too tall to be used in a micro-grow setting. They often stretch 2-3x their size during bloom, reaching upwards of 3m in some instances.

Autoflowering and indica strains, on the other hand, usually grow to be much smaller and more compact. It’s rare for indicas to stretch over twice their size during bloom, barring major stress conditions. Despite their smaller stature, the bushy nature of indicas allows them to produce just as much, if not more bud than some towering sativas. Autoflowering strains have a distinct advantage; these cultivars do not depend on a change in light cycle to initiate bloom, and their entire cycle from seed to harvest is usually very fast. This is why so many growers are cropping high-quality auto strains when attempting their first couple micro-grows. If after all this advice, you are still hell-bent on growing a sativa, check out the next section.


Training techniques are used by cultivators to limit the height and/or increase the yield potential of their plants. A method that is used a lot in cannabis grows is topping. Topping involves cutting off the main stem so two new main colas will form instead of one. This allows not only for bushier plants capable of producing denser, higher-quality colas, but also limits the height significantly. Topping can be done as soon as the plant has 4-6 nodes or three pairs of fully formed leaves. Topping can be done during the vegetative stage of growth, but should not be conducted during flowering.

Another technique that can help control height is ScrOG or screen of green. This method involves tying down and weaving new growth beneath a screen that keeps plants at a certain height. This will force the plant to grow more horizontally, giving the buds more light exposure and thus, potentially boosting yield.

Low stress training or LST is a bit similar to what we try to achieve with a ScrOG, but instead of tying the branches to the screen, branches are bent and restrained to grow in a certain position sans screen. This in turn creates more side branches, limiting apical dominance. Higher yields and more compact plants are to be expected.


In addition to the above, there are numerous other requirements growers must consider like nutrient feeding and pest/disease control. Hopefully, this article gave you a solid foundation on the logistics and tips surrounding a successful micro cannabis grow. Now, it’s up to you to conduct further research and get growing!

Micro-growing is a way for cultivators to crop high-quality bud in tight spaces. But how is it done?