How to grow marijuana outdoors: a beginner’s guide
Growing cannabis is a fun and rewarding experience, but it is also challenging and takes a certain amount of time and money. For a first-time grower with limited resources, an indoor grow is probably too costly of an option.
The good news is that a small outdoor garden can yield plenty of quality cannabis without a large monetary investment. If you have access to a sunny spot in a private yard or even a balcony, terrace, or rooftop, you can successfully grow cannabis.
This guide to outdoor growing will go over all the different factors you need to consider in order to set up your first outdoor marijuana grow.
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Benefits of growing weed outdoors
- Low costs: Relying on the power of the sun, you won’t need to spend a ton of money on an outdoor grow. You’ll need some soil, fertilizer, seeds or clones, and maybe a small greenhouse to get them started. You won’t need to pay for electricity for lights, AC units, or dehumidifiers, and you can even collect rainwater.
- Big yields: The sky’s the limit with outdoor plants—you can let them get as big and tall as you want, as long as they’re manageable. One plant can potentially yield up to a pound of weed! Growing a handful for yourself is plenty. With an indoor grow, your space is a lot more restricted.
- Environmentally friendly: Indoor grows can be wasteful, using a ton of electricity to power all those lights, fans, and other equipment. The sun and the wind are free!
- It’s fun and relaxing: Don’t underestimate the therapeutic value of gardening. It’s relaxing to spend some time outside, roll up your sleeves, and get your hands dirty for a while. And there’s nothing better than smoking something you grew yourself.
Step 1: Consider the climate
It’s crucial to have a good understanding of the climate in the area you’re going to grow. Cannabis is highly adaptable to various conditions, but it is susceptible to extreme weather.
Sustained temperatures above 86°F will cause your plants to stop growing, while continued temperatures below 55°F can cause damage and stunting to plants, even death.
Heavy rains and high winds can cause physical damage to plants and reduce yields, and excessive moisture can lead to mold and powdery mildew, especially during the flowering stage.
In addition to weather patterns, you need to understand how the length of day changes throughout the seasons in your area. For example, at 32° N latitude (San Diego), you will experience just over 14 hours of daylight on the summer solstice (the longest day of the year), while at 47° N (Seattle), you will have about 16 hours of daylight on the same day.
Understanding the amount of sunlight throughout the year is crucial to causing plants to “flip” from the vegetative to flowering stage, when they start to produce buds.
It’s good to utilize local resources, as experienced gardeners in your area will have a wealth of knowledge about growing flowers and vegetables, and that information can also be applied to growing cannabis. If you have some experience gardening and growing veggies, you will probably find that growing cannabis outdoors is a fairly easy endeavor.
Step 2: Pick a space for your outdoor grow
Choosing a space for your outdoor grow is one of the most important decision you’ll make, especially if you’re planting directly in the ground or in large immobile containers.
Your cannabis plants should receive as much direct sunlight as possible, ideally during midday, when the quality of light is best. As the season changes and fall approaches, your plants will get less and less sunlight throughout the day, which will trigger the flowering stage.
Having a constant breeze is good for your plants, and especially in hot climates. But if you live in an area with a lot of high winds, consider planting near a windbreak of some sort, like a wall, fence, or large shrubbery.
Finally, you will want to consider privacy and security. A lot of people want to conceal their gardens from judgmental neighbors and potential thieves. Tall fences and large shrubs or trees are your best bet, unless you live in a secluded area. Also, most state laws require that you keep cannabis plants concealed from the street.
Some growers plant in containers on balconies or rooftops that are shielded from view, while some build heavy-gauge wire cages to keep thieves and animals at bay. Whatever you decide, think about how big you want your final plant to be—outdoor cannabis plants can grow to 12 feet tall or more, depending on how much you let them go.
Step 3: Decide on cannabis genetics
The success of your outdoor cannabis grow will also depend on choosing the right strain to grow for your particular climate and location. If you live in an area with a history of cannabis growing, chances are good that many strains will successfully grow there, and some may have even been bred specifically for your climate.
Seeds vs. clones
Plants grown from seed can be more hearty as young plants when compared to clones. You can plant seeds directly into the garden in early spring, even in cool, wet climates.
The main drawback to growing from seed is there is no guarantee as to what you’ll end up with. If your seeds don’t come feminized, you could end up with both males and females, in which case you’ll need to sex them out to get rid of the males (only females produce buds).
Even when you do have all female plants, each will be a different phenotype of the same strain. To get the best version of that strain, you’ll need to select the best phenotype, which can be a lengthy process. A lot of beginning growers start with feminized seeds.
Depending on the legality of cannabis in your state, you may be able to buy clones or seedlings from a local dispensary. Some growers stay away from these because they feel they aren’t as sturdy as growing plants from seed.
Autoflowering seeds are another popular choice for outdoor growing, as they start blooming as soon as they reach maturity regardless of the length of day. You can either have a quick-growing crop, or fit multiple harvests into a year with autoflowering cannabis.
The downside to autoflowering cannabis is they tend to be a lot less potent.
Step 4: Acquire some soil
Soil is made up of three basic components in various ratios:
You can plant directly in the ground or buy soil and put it in pots. Cannabis plants thrive in soil rich with organic matter, and they need good drainage. If you decide to plant directly in the ground, you’ll need to understand your soil composition and amend it accordingly.
Heavy clay soils drain slowly and don’t hold oxygen well, so they will need to be heavily amended. At least a month before you plant, dig large holes where you’ll be placing your cannabis plants and mix in big amounts of compost, manure, worm castings, or other decomposed organic matter. This will provide aeration and drainage, as well as nutrients for the plants.
Sandy soil is easy to work, drains well, and warms quickly, but it doesn’t hold nutrients well, especially in rainy environments. Again, you will want to dig large holes for your plants and add compost, peat moss, or coco coir, which will help bind the soil together. In hot climates, sandy soil should be mulched to help with water retention and to keep roots from getting too hot.
Silty soil is the ideal growing medium. It’s easy to work, warms quickly, holds moisture, has good drainage, and contains a lot of nutrients. The best silty soil is dark crumbly loam—it’s fertile and probably won’t need any amending.
If you really want to ensure good results and minimize headaches, you can get your soil tested, which is easy and relatively inexpensive. A soil testing service will tell you the makeup and pH of your soil, notify you of any contaminants, and recommend materials and fertilizers to amend your soil.
Step 5: Get some fertilizer
Cannabis plants require a large amount of nutrients over their life cycle, mainly in the form of nitrogen, phosphorus, and potassium. How you choose to feed them will depend on the composition of the soil and your own methods.
Commercial fertilizers aimed at home gardeners can be used if you have a good understanding of how they work and what your plants need. But a first-time grower might want to avoid these, particularly long-release granular fertilizers.
Best nutrients for an outdoor grow
You can purchase nutrient solutions designed specifically for cannabis from your local grow shop, but they are usually expensive and can damage soil bacteria—they are generally composed of synthetic mineral salts and intended for indoor growing.
Organic fertilization takes full advantage of microbial life in soil and minimizes harmful runoff. There are many different natural and organic fertilizers available at local home and garden stores, like blood meal, bone meal, fish meal, bat guano, and kelp meal.
Start off with fertilizers that are inexpensive and readily available. Some of these materials release nutrients quickly and are easily used by the plant, while others take weeks or months to release useable nutrients. If done correctly, you can mix in a few of these products with your soil amendments to provide enough nutrients for the entire life of your plants.
Again, getting your soil tested can be very useful and will tell you how to amend your soil and what types and amounts of fertilizer you should use. If you are unsure how much to use, be conservative—you can always top dress your plants if they start to show deficiencies.
Step 6: Choose your containers
You may need to put all of your plants in containers if you don’t have great soil. Also, if you’re unable to perform the heavy labor needed to dig holes and amend soil, containers may be the only way for you to grow your own cannabis outdoors.
If you don’t have a suitable patch of earth to make a garden, containers can be placed on decks, patios, rooftops, and many other spots. If needed, you can move them around during the day to take advantage of the sun or to shield them from excessive heat or wind.
You can also use common cannabis nutrients designed for indoor growing because you will be using premixed soil. This will take much of the guesswork out of fertilizing your plants.
However, plants grown in pots, buckets, or barrels will likely be smaller than those planted in the ground because their root growth is restricted to the size of the container. In a broad sense, the size of the pot will determine the size of the plant, although it’s possible to grow large plants in small containers if proper techniques are used.
In general, 5-gallon pots are a good size for small to medium outdoor plants, and 10-gallon pots or larger are recommended for big plants. Regardless of size, you’ll want to protect the roots of your plants from overheating during warm weather, as pots can quickly get hot in direct sunlight. This will severely limit the growth of your plants, so be sure to shade your containers when the sun is high in the sky.
Step 7: Give your cannabis plants water
While outdoor cannabis gardens have the benefit of utilizing rain and groundwater, you will most likely need to water your plants frequently, especially in the hot summer months. Some giant cannabis plants can use up to 10 gallons of water every day in warm weather.
Growers who live in hot, arid places will often dig down and place clay soil or rocks below their planting holes to slow drainage, or plant in shallow depressions that act to funnel runoff toward other plants. Adding water-absorbing polymer crystals to the soil is another good way to improve water retention. Water your plants deeply in the morning so they have an adequate supply throughout the whole day.
If you live in a particularly rainy climate, you may need to take steps to improve drainage around your garden, as cannabis roots are susceptible to fungal diseases when they become waterlogged. These techniques include:
- Planting in raised beds or mounds
- Digging ditches that direct water away from the garden
- Adding gravel, clay pebbles, or perlite to the soil
If you’re using tap or well water, it’s a good idea to test it first. This water can contain high levels of dissolved minerals which can build up in soil and affect the pH level, or it can have high levels of chlorine which can kill beneficial microorganisms in soil. Many people filter their water.
Plants grown in hot or windy climates will need to be watered more frequently, as high temperatures and winds force plant to transpire at a quicker rate.
Remember that over-watering is a common mistake made by rookie growers—the rule of thumb is to water deeply, then wait until the top inch or two of soil is completely dry before watering again. An inexpensive soil moisture meter is a good tool for a beginner.
Step 8: Protect your cannabis plants
Without the ability to control the environment as easily as you can indoors, outdoor cannabis growers have to protect their plants from storms and other weather events that could damage or even kill plants.
Temperatures below 40°F can quickly damage most varieties of cannabis, so if you live in a climate where late spring or early fall frosts are a common occurrence, try using a greenhouse or other protective enclosure.
High winds can break branches and overly stress your plants. If your garden is located in a particularly windy spot or if you’re expecting a particularly heavy blow, set up a windbreak. This can be as simple as attaching plastic sheeting to garden stakes around your plants.
While helpful for watering your garden, rain is generally seen as a nuisance by cannabis growers. It can severely damage your crop and cause mold and mildew. You especially don’t want rain on your cannabis plants when they are flowering.
You can construct a DIY greenhouse or even just use plastic sheeting and stakes to build a temporary shelter over your plants when you know rain is on the way.
Protecting your cannabis garden from pests can be challenging. Depending on where you live, you might have to keep large animals like deer at bay by building a fence around your crop.
But the more difficult challenge is dealing with the vast array of crawling and flying insects that can attack your plants.
The best protection is to simply keep your plants healthy. Strong, vigorous cannabis plants have a natural resistance to pests that makes minor infestations easy to deal with. It’s also a good idea to keep your cannabis plants separate from other flowers, vegetables, and ornamentals, as pests can easily spread between them.
Examine your cannabis plants a few times a week with an eye out for pests. An infestation is far easier to deal with if caught early.
There are many organic pesticides designed for use specifically on cannabis, and beneficial insects are also a great option.
You should now have enough knowledge to successfully start your own outdoor cannabis garden. Cultivating and growing plants is an enjoyable and rewarding pastime, so remember, spend lots of time with your plants, and have fun!
Check out Leafly’s Growing section for more info on cannabis growing!
This post was originally published on June 21, 2016. It was most recently updated on April 2, 2020.
Growing marijuana outdoors can be less costly and challenging than an indoor grow. Check out our guide to learn more about the best outdoor grow setup.
Cannabis Micro Growing: Growing Great Weed in Tiny Spaces
Worried you don’t have the space to grow great weed? Well, don’t! With micro growing, you can grow superb bud in the smallest of spaces.
The new trend of micro growing weed is challenging the norms of how much space it takes to grow great cannabis at home.
Thanks to new and improved grow gear (especially grow lights) and an increase in knowledge concerning the cannabis plant, micro growers are able to churn out great harvests in extremely small spaces.
In this article, we’ll walk you through everything you need to know about micro growing, and set you up to grow great weed in (almost) any space.
Understanding the Basics of Micro Growing
Micro growing is regular indoor growing, but on a smaller scale. It’s all about producing top-shelf bud with all the flavour, aroma, and potency you want, but in confined spaces (such as small DIY tents, cupboards, bar fridges, or even hulled desktop computer towers). Alternatively, some growers opt to buy ready-made stealth grow boxes.
The minimum amount of space you’ll need to grow weed in a micro setup is 35 × 35 × 75cm. To accommodate the lack of space in a micro grow, you’ll have to make minor adjustments to your lighting and ventilation, the strains you choose to grow, your medium, and your watering/feeding schedule.
Using the Right Amount of Soil
Micro growing is usually done using soil, as setting up a soilless or hydro system in a space as small as a mini-fridge can be very difficult. So, to accommodate the lack of space that qualifies a micro grow, you’ll want to use less soil to prevent your plants from outgrowing their small room or tent.
The root system is a crucial part of the plant, and its size has a great influence on how tall the plant will grow. Most plants tend to occupy the same amount of space below the ground as they do above. In a micro grow, we can use this correlation between the size of the root system (thus, the amount of medium) and plant size to control the growth of our cannabis plants and match it to our spatial limitations.
Below you’ll see how different pot sizes will impact the height of your cannabis plants:
Note that these figures are just estimates, and the exact size of your cannabis plants will vary depending on their genetics. Also, keep in mind that plants grown in small containers will need to be fed and watered more regularly than plants grown in larger containers with access to more soil.
For micro growing, we generally recommend sticking to 3l pots. However, we’ve seen some growers working with slightly larger spaces use up to 9l pots. How big or small you choose to go with your pots is up to you; just keep in mind that using bigger pots will likely restrict the number of plants you can grow (but more plants won’t necessarily translate to a bigger micro grow yield).
Finding the Right Grow Light
First and foremost, you’ll want to turn to LEDs for micro grows. HPS and HPI lights simply aren’t suited to these small grows as they produce far too much heat.
For the best results, we recommend using LED panels. A 15W panel is capable of producing op to 3000 lumens while producing almost no heat and taking up virtually no space (the panel measures just 130 × 110mm).
Alternatively, we recommend using any small 60W LED panel for your micro grow. Depending on just how small of a space you’re growing in, you’ll likely never need to keep this panel running at 100% capacity. We recommend keeping it at 25–50% to help control your plant’s stretch during veg, then turning it up to 50–75% during bloom, depending on the plant’s stretch. You can also control the panel’s light schedule using a controller, which is app-operated.
Properly Placing Your Grow Light
One common question micro growers face is this; where do I place my grow lights?
Traditional indoor grow setups place the main grow light directly above the canopy. But, since micro growers are often working with extremely small spaces, this setup might not always be the best option.
In small vertical spaces (like a grow box, small cupboard or furniture piece, or computer tower), you’ll usually be better off placing your main grow lights along one or multiple sides of your plant. This will allow you to grow a bigger canopy, improve light penetration through the canopy, and prevent plants from stretching towards the top of your grow space.
For even more control, you may want to consider building two separate grow boxes; one for veg and another for bloom. In the veg box, you may be able to get away with placing your grow light right above your plant, as light penetration isn’t as much of an issue during veg as it is during flowering. Remember to keep in mind the speed at which your plants grow, and try to find strains that grow at a speed that suits the size of your space.
If you do opt to install your veg light above your plants, remember to keep it at the right distance and intensity. If your grow light is too close or too strong, plants are likely to develop very short internodes and might show signs of light stress. If, on the other hand, your light is too far or too weak for your plants, they’re going to stretch and develop long internodes.
In your bloom box, however, we recommend placing your grow light along the sides of your plants. This will provide the best light penetration and allow you to grow a longer vertical canopy of buds. We also recommend using a vertical net to keep your plants centered. You can also use this net to train your plants gently and control their growth as you see fit, given your space.
How to Manage Ventilation and Smell in a Micro Cannabis Grow
While it might seem like a trivial detail, properly ventilating your cannabis micro grow is a must. When working with such a small space, air can quickly become stagnant and start creating a lot of problems for your plants. This is because plants consume the CO₂ in their environment for photosynthesis. When growing in such small spaces, your plants have very limited access to fresh, CO₂-rich air, making proper ventilation a must for healthy plants.
Luckily, ventilating a cannabis micro grow space is easy.
If you decide to build your own micro grow setup, all you’ll need to keep your space ventilated is a small outtake fan, like this 24V Brushless Centrifugal Blower. While it might not look like much, this tiny fan will do a perfect job at removing old, stagnant air from your grow space. For the best results, we recommend installing it directly above your plants.
If you’ve got enough space, you may even want to consider keeping a small hand-held fan inside your space to keep air circulating properly around your plants.
For even better ventilation and air circulation, we recommend installing a small intake fan at the bottom of your micro grow setup. A high-speed cooling fan, for example, will let a constant influx of fresh air into your micro grow space.
Because micro grows usually only allow you the space to grow one small weed plant (or two), you shouldn’t need to use carbon filters to manage the smell of your operation. However, if you want to be extra safe, installing a carbon filter to the outtake fan we mentioned above is simple. The filter needs to be installed in front of your outtake fan, and therefore may rob you of some space inside your mini grow room/box.
How to Water Cannabis Plants in a Micro Grow
Watering your cannabis plants in a micro indoor setup can be tricky due to the lack of space. If you’re building your own micro setup, take this into consideration and try to leave enough space around the base of your plants so you can water them comfortably. Remember that water splashing up onto the foliage and buds of your plants can cause fungal issues, so you’ll want to avoid it at all costs.
If you’re growing in a truly tiny space—one where you can’t walk around or get a good position over your plants—make sure you can remove your plants for watering so you don’t end up making a mess of your space.
Given the small scale of a micro grow, we generally don’t believe they warrant the installation of any automatic watering systems. Just have the patience to manually water your plants using a small watering can or bottle.
How to Use Growing Techniques in a Cannabis Micro Grow Setup
Micro grows typically call for smaller, bushier plants. In order to achieve this kind of structure and produce decent harvests in such small spaces, you’ll want to employ some growing techniques like LST, HST or ScrOG, and Defoliation. Below, we’ll share some basic tips on how to adapt these techniques to a micro grow setup.
LST is easily one of our favourite grow techniques, and can come in super handy when growing in small spaces. The only way your LST technique might vary when micro growing is in how you direct your plant’s growth. Remember, the goal of LST is to open up your plant and improve light penetration. Think about how you’ll achieve that given the lighting in your micro grow room.
HST (Topping, Super Cropping, FIM, etc.)
High-stress techniques may be a little trickier to apply to a micro grow. Topping or fimming, for example, create multiple dominant colas, which may not be ideal in small, narrow vertical indoor gardens.
If you’re growing in a short yet wide space (like a shelf, for example), you may want to use super cropping or fimming early on to create a short canopy packed with thick colas. In fact, super cropping may come in handy in either case, as it strengthens your plant in time for bloom and, like LST, can direct growth in the right direction to make better use of your lights.
Screen of green is another of our favourite training techniques, and you’ll be glad to know you can take advantage of it even in small micro cannabis gardens. If you’re working with a narrow vertical space with lateral lights, for example, using a vertical screen can be one of the best ways to create a big canopy that receives a ton of light.
In a short, horizontal micro grow cabinet, on the other hand, you can use ScrOG as you would in a regular indoor garden to create a thick, even canopy that, come harvest time, will be loaded with sticky buds.
Defoliation is essential to micro growing. In a narrow, vertical grow room with lateral lights, defoliation will help you clear unnecessary foliage and ensure all parts of your plant get enough light to develop big, thick buds.
When to Switch Your Micro Grow Room to Bloom
In general, we recommend you flip your vegetative cannabis plants to bloom once they’ve grown to half of the height of your micro grow box. This will ensure they’ve still got enough space to accommodate their pre-bloom stretch without growing too close to the top of your box/room.
Remember that the rate at which your plants grow is directly related to the amount of light they receive. More light will result in shorter internodes, while plants grown with less light will stretch, resulting in larger spaces between each node. You may need to play around with the lighting in your micro grow room to find the sweet spot for each of your strains.
Micro Growing Cannabis: Expect Realistic Results
As with any cannabis grow, it’s important to set yourself some realistic expectations regarding the size and quality of your harvest, as well as the amount of time it’ll take you to get from seed to harvest.
In general, growing in a small 35 × 35 × 75cm space using a rough average of 30W of light throughout your entire grow, you can expect to harvest between 25 and 45g, depending on the strain, your feeding routine, training techniques, and skill. You’ll usually be able to go from seed to harvest within 3–4 months, depending (obviously) on your light cycle and the genetics of your plants.
Finally, the cost of setting up your micro grow box/room will vary greatly. If you choose to build your own micro grow space, you may be able to do so relatively cheaply (keep in mind that your LED panel will easily be the biggest upfront cost).
Choosing A Suitable Strain
When it comes to micro growing, choosing the right strain is very important due to the limited space available. One of the things to watch out for is the height of your cannabis strain. Sativas grow higher and more slender than indicas, which tend to be short and bushy.
Furthermore, during the flowering phase sativas undergo a 200-300% increase in height, while Indicas increase only by 50-100%, which shows that indicas are more compatible with micro growing.
Another reasonable option would be autoflowering strains. No matter what the conditions, autoflowering strains stay small due to their genetics (a great many of them even smaller than indicas) and aren’t dependent on the light regime, which means they will have a shorter harvest time.
3 Great Strains for Micro Growing
Of course, some genetics are more suited to micro growing than others, and the following three are prime examples of quality picks. You’ll notice these strains all have something in common: they’re autoflowering.
Royal Dwarf truly is a miniature cannabis specimen that can remain at tiny sizes of 40cm tall when trained in the ways mentioned above. This plant was bred for one reason and one reason only: stealth. Growers can easily cultivate multiple Royal Dwarf plants in their home without a single suspicion being raised. She can easily be grown within modified kitchen cupboards, wardrobes, boxes, and computer towers. Small LED lights can also be used within these tiny spaces to avoid giving off too much heat. Royal Dwarf is essentially the autoflowering version of the legendary Skunk, and was made using a Skunk strain along with a specific ruderalis cultivar. She offers stimulating but subtle sativa highs fuelled by THC quantities of 13%. She can therefore be smoked all day long whilst allowing the user to stay on top of their game and not get too high. Her small yet compact flowers offer sweet and citrus tastes.
Royal Dwarf will be ready to harvest a mere 8–9 weeks after seeds have been germinated. Plants grown indoors will provide yields of up to 200g/m² and won’t exceed 70cm in height. Plants grown outdoors within garden beds or guerrilla grow spots will produce harvests of 30–80g/plant and reach heights of between 50–90cm.
Think you haven't got the space to grow weed? Think again. With our guide on micro growing, you can grow top-shelf bud at home in even the tiniest of spaces.