Want to try your hands on cannabis micro growing? Learn everything about growing a small weed plant indoors and outdoors. I have an indoor growroom and in my recent harvest I found seeds in the buds, but I’m sure there are no male plants in the room. 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.
Cannabis Micro Grow: Growing a Small Weed Plant
Many people are taking up growing their own cannabis plants indoors these days. However, not everyone has the space to be growing large marijuana plants at home. Micro growing allows both new and experienced growers to achieve high yields while using as little space as possible. Here’s our guide to starting your own cannabis micro grow.
What is Cannabis Micro Growing?
Micro growing is a cannabis growing setup that takes up only a small amount of space while achieving very high yields. With micro growing you can turn compact spaces such as closets, boxes and so on into small grow rooms. All you need is to choose the right conditions and strains, and you will be able to successfully grow high yields in even the smallest of spaces.
Advantages of growing small cannabis plants
Perhaps the biggest advantage to micro growing is that it can produce large yields while only using a minimal amount of space. It is ideal for new growers as it’s very compact and manageable, plus it is a more cost-effective way to grow plants. In addition, micro growing allows you to keep your cannabis plants hidden, which can be an advantage depending on where you live.
Expected Micro Grow Yield
If using the minimum recommended space of 35 x 35 x 75 cm space to grow your plants with 30W of light used throughout, you should expect a yield of around 25 to 45g within a few months. This depends on the type of strain you use as well as additional factors such as feeding regimes, training methods, and your skill as a grower.
(Stealth) Micro Weed Setup: What you Need to Grow a Small Weed Plant
While you won’t need super expensive equipment to start micro growing your plants, you will need some basic and reliable gear in order to succeed. Ensure you have an adequate space for growing your plants: 35 x 35 x 75 cm is the bare minimum. Purchase basic lighting as well as equipment for ventilation and temperature control. Have the right soil and nutrients on hand and make sure the grow space is kept sterile at all times. Finally, choose a small pot to ensure your plants do not grow too large.
In addition to the materials listed above, you need to consider what kind of strain you will use. Because your space is limited, you need to keep in mind that not all strains are suitable for micro growing. For example, sativa strains have a tall and thinner growth habit than indica strains, so these work best in grow areas with more height, while indica strains tend to grow short and bushy and work well in wider grow spaces.
Some small grow strains we recommend for micro growing are:
How to grow a Small Marijuana Plant
1. Get your grow setup ready
The first thing you need to do in order to set up your micro grow is to choose the right space.
The absolute minimum size you should use for a grow room is 35 x 35 x 75 cm. Work out how many pots you will be able to fit in your space, keeping in mind that the smaller the pot, the smaller the growth.
A 3 to 4 liter pot will allow for a plant the size of 35-50 cm without training, while a 10 liter pot will allow for a plant up to 110 cm.
We recommend smaller pots to avoid overcrowding, however if you plan on using larger pots make sure you have enough space for your plants, particularly in terms of height.
Next, set up your lighting. LEDs work best, but can bleach your plants if put too close. A 15W LED panel will do well and produce no heat, or you could try a 60W LED running at 25-50% during the vegetative stage and 50-75% during the flowering stage.
While you can use a normal 30W light bulb for your plants, keep in mind that these can produce heat. Install the lights above the plants or on the side of the canopy and use an app operated controller to set up the light schedule.
The next thing to set up in your grow room is a ventilation and air exchange system for your plants. Your plants need CO2 for photosynthesis, and proper ventilation will give them enough CO2 while ensuring the air within your grow room does not become stale, which in turn would risk bugs and diseases.
For more compact grow spaces, a small 24V outtake fan above the plants will be enough to remove stagnant air, while a small intake fan at the bottom of the room will draw in fresh air.
Larger grow tents can even use a handheld fan for even greater air circulation. While this setup should be enough to neutralize any strong plant odors, you can also try installing a carbon filter near the outtake fan just in case, as well as a system for monitoring the internal temperature.
Finally, check that you have the right mix of nutrients for your plants. Plants need both macro and micro nutrients in addition to water in order to grow well. Be aware that the smaller the pot, the more frequently you will need to feed the plant, so keep this in mind for the growing stage. Once done, you can gather your cannabis seeds and mix the soil or similar medium within each pot to start your micro grow.
2. Grow your plants
Once your grow setup is in place, and you have your seeds ready, you can start growing your plants.
To start the germination process, ensure the seeds remain damp but do not overwater. Keep the temperature warm (around 24-26C) and leave the lighting off to save power. Within a maximum of 10 days, your plants should start sprouting.
Tip: Please review our guide on germinating weed seeds for more information on this process.
Once germinated, make a small indentation in the soil or growing medium of about 2 cm deep. Place the germinated seed in the small hole with the roots facing downwards, then cover it with 3-4 mm of soil or growing medium.
Tip: See our guide on planting weed seeds after germination for more details on this process.
Remember to keep the humidity of your grow room around 50-60% and the temperature between 18-25C for proper growth. Set your lighting cycle to 18/6 during this stage where the plant is growing and in its vegetative state. Remember to set your LED lighting to 25-50% if using a 60W panel. Ensure the plant is watered and fed nutrients frequently.
Remember that smaller pots mean smaller roots, so you will need to divide up feeding and watering into smaller portions given at regular intervals. We also recommend removing each pot temporarily for water and feeding, as trying to manage this inside your grow space may prove difficult and could pose a risk to the plants.
Tip: If you are new to growing plants indoors, we recommend checking out our guide for indoor weed growing for more information.
If at any stage you decide to bring your plants out of their grow space, so they can grow naturally outdoors, we recommend that you check outside conditions first as well as consider the time of year. Late spring is usually the best time for growth, and any time after the summer solstice when the days become shorter will help induce the flowering period when ready.
3. Train your plants
Because your grow area will have limited space, you will almost certainly need to train your plants in order to control their size. This will not only help you keep your micro grow at a manageable size, but also allow you to increase your yields.
Low stress training
The first training technique you can try is Low Stress Training (LST). This training method involves tying your branches back to control the direction of growth. If done correctly, your branches should grow outward rather than vertically.
This is a useful technique if you have limited height in your grow area. In addition, it is a good way to ensure more of your plant is exposed to light, potentially increasing your yield.
Tip: To find out more about this technique, read our guide on Low Stress Training.
Some other methods you can try to include Sea of Green (SOG) and Screen of Green (ScrOG). SOG involves keeping as many plants together in a small space and training your plants to reach harvest time quickly. ScrOG, on the other hand, involves putting a trellis above your plants. This not only controls the height of your plants, but also opens them up to more light and airflow. Both methods are designed to increase your overall yield.
Tip: Read our guides on the Sea of Green method and Screen of Green method for more information.
High stress training
There are several High Stress Training (HST) methods that can work well with your plants as well. These methods include topping, fimming and super cropping.
Topping involves cutting off the top of the main stem above the fifth node so that the plant can develop more colas and a higher yield. Fimming is similar to topping: in fact, FIM stands for “F**k! I missed!”, implying that a clumsy grower while attempting to top their plant stumbled on a new method. This method involves cutting off around 75% of the apical bud, found at the top node of the plant. If successful, this should produce multiple colas.
Tip: To learn more about these two methods, please read our guide on Topping vs Fimming.
Another HST method is Super Cropping. This training method involves pinching and squeezing the stems of the plant to make them stronger and able to produce more buds. Read more in our super cropping guide to find out more.
You can try one or a combination of these methods to achieve a good yield from your micro grow. Go ahead and experiment to see what works best for you.
After a period of weeks, you will be able to harvest your plants: this can be up to 10 weeks for indica plants and 14 for sativa plants. Autoflowers can usually be harvested just 10 weeks after planting.
To see if your plants are mature, check the leaves: if they are yellow or curved, that is a good sign that they are ready for harvesting. In addition, the pistils may turn reddish or brown and the trichomes turn milky white. The buds may even change shape into thicker versions of themselves.
Tip: Read our guide on when to harvest weed plants for more information.
To begin the harvesting process, flush the roots with plenty of water to remove any nutrients. Set up your harvest room, keeping the temperature around 21C and the humidity below 50%. Ensure you have the right tools on hand for harvesting your plants (gloves, scissors, trays, etc.). Cut the ripe buds from the main stem and branches, making sure to leave the immature ones for another five to ten days. Avoid damaging the flowers. Trim your weed and begin drying them to improve the flavor.
Tip: Read our guide to find out more about how to harvest cannabis plants. Once done, you can prepare your grow space to begin again.
Let’s Grow Some Small Weed Plants
Now that you know the process involved in micro growing cannabis, you can try the process for yourself. Remember that smaller growing seeds work best for micro grow setups. Check out our range of small growing weed seeds to try this for yourself.
I have an indoor growroom and in my recent harvest I found seeds in the buds, but I’m sure there are no male plants in the room. I’ve heard that light leakage can cause plants to become hermaphrodites. Is this true, and if so, do you have any tips for avoiding this?
Cannabis plants are monecious. This means they have the ability to be either male or female. Or in the case of hermaphroditism, they can be both. The reason to make sure there are no males or hermaphrodites in your garden is because male flowers make pollen. When pollen touches the white hairs on a flower, it makes a seed, and seeded weed gives you headaches. Even though there are reasons in nature hermaphroditism could be important, such as continuing the species in case there is no male present, hermaphroditism is generally a bad thing when talking about cannabis plants.
Light poisoning is the most common cause for a normal plant to hermaphrodite.
Light poisoning refers to the flowering night cycle of a plant being unnaturally interrupted with light. The best way to prevent this is to close yourself inside your darkened room during the daylight, and then after allowing a few minutes for your eyes to adjust to the dark, check for any light leaks from covered windows, door jams, etc. Also cover all timer and appliance lights with tape.
Negative stressors can combine with small interruptions of the light cycle to cause hermaphroditism, especially with less-stable, clone-only hybridized strains. When the night cycle is abnormally interrupted, it sends a mixed hormonal signal to the plant. This can cause a full female plant to throw some male flowers. Male flowers are easy to identify, especially when side by side with female flowers. Male flowers look like small bunches of bananas, which will take a week or two to swell before they burst and release their pollen.
Finding a hermaphrodite in your growroom can happen at any stage of the flowering cycle and is indicated by the presence of male flowers growing on the same plant as female flowers. As with all species in nature this can occur in varying degrees. A plant can become slightly or majorly hermaphroditic. In cases where singular male flowers are found between the branch and stalk nodes, you should be diligently removing them as they grow. You must re-inspect the plant top to bottom every few days to be sure pollination and seeding doesn’t occur. If you find male flowers (anthers) actually growing from within the female flowers (buds) the situation is a little more dire. You can still remove all the male anatomy as it appears, but it will be harder to find and much more prevalent. This is a horrible discovery that leads to a tough decision: Should you let the plant live and risk the whole crop being ruined by seeds?
In either case, once hermaphroditism has compromised the safety and purity of your sensimilla, the plant should not be propagated further. Remember, once a hermy, always a hermy. The plant pictured here is in the tenth and what should have been the final week of ripening, but a timer failed and one light stayed on continuously for almost two weeks, causing this vegetative regrowth. Because the light was continuous, the plant made no pollen. This method of re-vegging can be used to save a flowering plant you have no copies of, but be careful, as this may cause some strains to hermaphrodite.
Purposefully causing a plant to hermaphrodite is called selfing. Gibberellic acid or colloidal silver is typically sprayed onto the female plant. This technique is used to make feminized seeds and uses the plant’s ability to be both male and female to force a female plant to produce male flowers. The pollen contained in these male flowers can only produce female seeds. Just keep in mind that feminized plants should not be used for breeding, as they were produced without a true male, making them genetically inferior.
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. A common query when designing a micro grow is where exactly the lighting should be placed. Traditional grow rooms have the main light fixtures placed directly above the plants, with auxiliary lights sometimes added in various places throughout the grow room.
Since micro grows are often short on space, this traditional method may not be the best option. If you are going to grow in a tall vertical space with a small footprint it may be better to hang your light alongside the plant. This can be done on one side, but if possible it is better to cover multiple sides of the grow compartment with light sources. This helps with light distribution and penetration through the entire canopy and can help combat any stretching issues you may encounter when lighting from above only.
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|
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. The figures shown in the table above are just a general guide. Exact plant sizing will be dependent on which strain to type you opt to grow, and which growing techniques you implement. For micro grow setups, pots no larger than 2 to 3 liters are recommended. Some growers prefer to use larger pots and grow fewer plants, but a good general rule of thumb for maximizing yields in small grow areas is to go with more plants in smaller pots.
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.
Sativa dominant strains are known to increase in size by up to 200 to 300% during the flowering stage, whereas most Indica dominant varieties show increases in size closer to 65 to 130%. Certain Autoflowering strains are great for micro growing as they can be grown under multiple light schedules with some strains having a tendency to stay small and compact.
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. Keep in mind that auto-flowering plants tend to struggle with any aggressive plant training. High-stress training can halt vegetative growth for a few days all the way up to a week or more. These techniques are fine for photoperiod plants as they can be forced to stay in the vegetative stage by keeping the light schedule to 18/6.
Autoflowering plants have an inbuilt timer, with the vegetative stage usually lasting 5 to 6 weeks before they automatically start flowering (hence the name autoflower), no matter what light schedule they are grown under. Be sure to treat autoflowering plants like the princesses they are, keep any stress training to a minimum, and handle them with the care they deserve!
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!