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, using our weed seeds. Here’s our guide to starting your own cannabis micro grow.

> Quick jump to: How to grow a small marijuana plant

What is Cannabis Micro Growing?

Micro growing cannabis is a 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 for your cannabis plant.

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 weed 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. While you still might have to mask the scent, if you grow small cannabis plants you can ensure your babies will stay out of sight.

Expected Micro Grow Yield

If using the minimum recommended space of 35 x 35 x 75 cm (14 x 14 x 30 inches) 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 photoperiod plants grown from feminized seeds tend to be higher yielders compared to when you grow cannabis from auto feminized seeds indoor. Additional factors such as feeding regimes, training methods, and your skill as a grower of small plants also play a significant role in the overall yield.

(Stealth) Micro Weed Setup: What you Need to Grow a Small Weed Plant

While you won’t need super expensive equipment to start cannabis 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 (14 x 14 x 30 inches) is the bare minimum.

Purchase basic lighting (LED grow lights are one of the more convenient options) 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 cannabis plants do not grow too large.

Suitable strains

In addition to the materials listed above, you need to consider what kind of small weed plant 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, feminized sativa strain seeds have a tall and thinner growth habit than indica cannabis seeds, 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:

1. Blue Dream autoflower
2. Critical Purple autoflower
3. Gelato feminized
4. Snow White feminized
5. Zkittlez Autoflower

How to grow a Small Marijuana Plant

1. Get your grow setup ready
2. Grow your plants
3. Train your plants
4. Harvest

1. Get your grow setup ready

The first thing you need to do in order to set up your cannabis micro grow is to choose the right space.

Grow tent

The absolute minimum size you should use for a grow room is (14 x 14 x 30 inches). 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 (0.8 to 1 gallon) pot will allow for a cannabis plant the size of 35 to 50 cm (14 to 20 inches) without training, while a 10 liter (2.6 gallon) 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.

Lights

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 cannabis plants, keep in mind that these can produce heat. Install the lights above the plants or on the side of the plant canopy and use an app operated controller to set up the light schedule.

Ventilation

The next thing to set up in your grow room is a ventilation and air exchange system for your marijuana plants.

Your tiny 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 cannabis 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.

Nutrients

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 cannabis plants.

Germination

To start the germination process, ensure the seeds remain damp but do not overwater. Keep the temperature warm 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.

Planting

Once germinated, make a small indentation in the soil or growing medium of about 2 cm (0.8 inches) deep. Place the germinated seed in the small hole with the roots facing downwards, then cover it with 3-4 mm (0.11 to 0.14 inches) of soil or growing medium.

Tip: See our guide on planting weed seeds after germination for more details on this process.

Growing

Remember to keep the humidity of your grow room around 50-60% and the temperature between 18 to 25 °C (64 to 77 °F) for proper growth.

Set your lighting cycle to 18/6 during this stage where the cannabis plant is growing and in her 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.

Keep in mind 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, when growing photoperiod plants.

Tip: Read our guide for growing weed outdoors.

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.

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.

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.

4. Harvest

After a period of weeks, you will be able to harvest your plants: this can be up to ten weeks for indica plants and fourteen for sativa plants. Autoflower cannabis plants can usually be harvested just ten 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 21 °C (70 °F) and the humidity below 50%.

Ensure you have the right tools on hand for harvesting your cannabis 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.

What have we learned?

We've explored the art of cannabis micro growing, a compact, cost-effective, and stealthy method of cultivation that enables impressive yields in small spaces.