How to Grow a Small Weed Plant

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What is Micro-growing?

Wouldn’t it be wonderful if you lived in a place where the sun always shined and growing cannabis whether on your property or anyone else’s was always a welcome activity? Some like to call that place Nirvana.

For the rest of us living on planet earth, however, finding suitable space and resources to grow weed can often be a challenge. Fortunately, cannabis is a resilient type of plant that can be grown in a variety of settings including very small spaces like cupboards and closets.

And that’s what micro-growing is really all about–raising flavorful, aromatic, and potent plants and getting a decent yield out of the very limited space they are grown in.

How to Micro-grow a Small Weed Plant

It should go without saying that small growing spaces require smaller-sized plants. It also means adjusting the techniques and resources you employ to try to produce good yields under more constrained circumstances.

Here we’ll walk you through the basics.

Pick Your Strain of Cannabis

If you’re going to do a micro-grow, then you need to choose a strain that produces smaller-sized plants. There are three basic types of cannabis, including Indicas, Sativas, and auto-flowering cannabis strains.

Autoflowering Cannabis vs. Photoperiod Cannabis

When we think of marijuana, what usually comes to mind is either Sativas or Indicas. One tends to grow tall (Sativas), the other, short and bushy (Indicas).

Their leaves are also a bit different, and they each have different qualities. Sativas tend to be energizing, while Indicas tend to bring on calm and relaxation.

Both types are photoperiod cannabis, meaning they rely upon natural sunlight or a specific amount of manufactured light in order to move through each growing stage.

We explain how to grow a small weed plant

“Autoflower lowrider popular cannabis, famous marijuana. Source: Author: Yarygin”

Autflowering plants, on the other hand, have an internal clock that moves them into the flowering cycle despite any fluctuations in light. Their growth cycles are shorter meaning they get to harvest in an average of 80 days, and they tend to have a compact stature, often smaller than most Indica plants.

However, auto-flowering cannabis plants tend to produce smaller yields with lower THC content.

Indica vs. Sativa Growing Styles

If you are going to try your hand at micro-growing, it’s best you stick with either Indica or auto-flowering strains. In fact, if you’re interested in raising a small cannabis plant that is a combination of the two, try Royal Dwarf, a cross between an Indica-leaning hybrid and an unknown autoflowering specimen.

Royal Dwarf plants grown indoors are small, staying under 70cm in height and they produce a moderate THC content.

Sativas, in comparison, are simply not the best choice. These slender plants tend to grow much taller than their shorter, bushier Indica cousins.

You may have what you think is a small Sativa plant only to find it grow another 200 to 300 percent during its flowering phase.

Select Your Grow Location

Wouldn’t it be great to grow your weed wherever your darn well felt like it?

Cannabis in a Grow Tent

If size control is a must but you still have some wiggle room, then using a grow tent is a good option. The mesh intake holes in these tents help protect the buds on your plants from unwanted debris getting stuck to them.

Even small plants need added protection and a grow tent allows you to play Mother Nature and control the amount of light, humidity, temperature, and other factors that can impact the health of your plants.

Growing Cannabis Outside

Small weed plants are usually selected due to the grower’s limited amount of space available. Either that or a need to be discreet. Or a combination of the two.

Image of cannabis sativa plant male flowers

“Cannabis sativa plant male flowers. Source: depositphotos. Author: jessicahyde”

If you have your heart set on growing outdoors au natural and the law permits it, then you might want to go with a strain that can reach the sky. Lights, no matter how good they are, can never quite match the power of the sun, and some Sativa plants can grow HUGE.

If you’re growing outdoors, you may also want to go with a larger strain as the climate will likely limit you to only one harvest.

Choose Your Pot Size

If you want to keep your plants small in size, then you’ll need to control the amount of soil they are permitted to grow in, then match a pot to best accommodate that amount of soil. You don’t want to use over-large pots, but nor do you want to go too small either.

A too-small pot can cause your plants to become root-bound resulting in stunted growth or even early death.

As a general rule, you can limit your plants to 60mm in height by planting them in no more than five liters of soil. If you want your plants smaller–say, for example, 24cm in height, limit the soil to two or three liters.

In addition, no matter the size of the plants you are trying to achieve, be sure to choose a soil with a balanced N-P-K blend with a well-tuned pH and one that includes healthy organics like earthworm castings, bag guano, or fish emulsion. You can find a variety of soils online that are good for growing cannabis, but our hands-down favorite is Happy Frog Soil.

The Cannabis Vegetative Stage

The vegetative stage is basically your plants’ adolescence. This is when it does most of its growing getting tall and healthy and strong.

Branches will form and leaves will unfurl, but you won’t see any flowers or buds during this phase of growth. If you want to keep your plants on the smaller side, you need to limit this vegetative stage to only a few weeks at most.

While the strain, pot size, and amount of soil you choose will have a direct impact on the size of your plants–as well as water and good airflow–the type of lights you use, and how much of it you give your plants during this time will also provide some control.

While there are a variety of different lighting types to choose from for indoor cannabis grows, LEDs (Light Emitting Diodes) tend to be the favorite amongst micro-growers. These inexpensive lights provide a whole light spectrum that can be used not only during the vegetative stage but also later when your plants are starting to flower.

Close-up of medicinal Cannabis

“Marijuana Leaves on Top of Plant. Source: Author: VictoriaBee”

They also generate less heat than their counterparts, an important factor to consider for tight spaces where excess heat can cause plants to burn.

Non-auto-flowering plants will remain in the vegetative stage so long as you feed them light 18 hours a day and darkness for the remaining six. Once you move to a 12-hour on/12-hour off schedule, they’ll begin to flower.

Therefore, cutting back on the hours of light will shorten the vegetative stage and help to keep your plants on the smaller side. You should also defoliate your fan leaves occasionally as that will slow growth and often results in a shorter, bushier plant.

The Cannabis Flowering Stage

This stage, as the name suggests, is when your plants are starting to bloom. During this phase of your micro-grow, you’ll want to move your lights to be along the sides (rather than overtop) of your plants.

This practice allows for better light penetration, which is crucial. You might also want to employ the use of a vertical net to gently control the direction of growth.

How much Cannabis will you Harvest?

That’s really what it’s all about, isn’t it? While micro-grows offer the advantage of producing a yield out of a small grow space, invariably that yield will be smaller.

It is, however, possible to estimate the yield from your plants. You can do so based on the size of your pots or on the wattage of lighting used.

Lighting estimates are generally more reliable, and you can expect to harvest about a gram of dried bud per watt. This will, of course, depend on the strain of your plants and how well you care for them overall.

Expect to go from seed to harvest in about three to four months on average.

If you want to estimate your yield based on pot size, the height of your plants will be the indicator. What is the yield you’ll get from 36-inch plants?

Possibly as much as 100 grams. What kind of yield can you expect from 12-inch plants? Considerably less.

FAQs about Growing a Small Weed Plant

Is there a difference between auto-flowering and feminized seeds?

There is. If you’re growing indoors with feminized seeds, then you’ll need to change the amount of light you feed your plants in order to push them into the next stage of growth. Auto-flowering seeds, on the other hand, will move to the flowering stage on their own.

How much light do auto-flowering plants need?

Outdoors, auto-flowers thrive on a minimum of six hours of direct sunlight. If you’re growing your plants indoors, a good mix is 20 hours of light followed by 4 hours of darkness a day.

Is there a recommended size pot for auto-flowering plants?

Autoflowering plants are typically grown in 1/2-gallon to 5-gallon pots. The larger the size, the larger your plants will be.


If you’ve always wanted to grow your own weed but feared your limited space would be a deterrent, now is the time to set that fear aside! Hopefully, this guide will get you on your way to taking the plunge with your own small growth.

Here’s to a high yield!