Updated: Mar 17, 2022
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.
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.
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!
This post was originally published on June 21, 2016. It was most recently updated on April 2, 2020.