best soil for growing cannabis outside

For most first-time gardeners, we recommend buying a quality potting soil that will provide your plants with enough nutrients to get them through most of their growth cycle without having to add many amendments. This pre-fertilized soil—often referred to as “super-soil”—that can grow cannabis plants from start to finish without any added nutrients if used correctly.

It’s fun and relaxing.

Weed plants will need full, direct sun for at least 6 hours a day. You may have a backyard, but it might not be great to grow there if it doesn’t get full sun every day.

Heavy clay soils drain slowly and don’t hold oxygen well, so they will need to be heavily amended. A few weeks before you plant, dig large holes where you’ll be placing your weed 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.

Roof: This can be great for sun but may have too much wind.

Clay soils.

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.

Most outdoor weed growers will either dig a hole and add fresh soil for the plant, or grow their weed in pots. This will allow you to better control the growing medium and the amount of nutrients your plants receive.

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.

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.

Low costs.

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.

Most potting soils used in gardening are loam soils. If you’ve ever worked with potting soil, you’ll know that its composition is rich and diverse, and it looks dark and hearty. Beyond texture and color, the soil should smell rich and alive.

Here are some important considerations before starting an outdoor marijuana grow.

These are just some examples of amendments commonly used in different types of soils. Heavily amended soils will have long lists that break down all organic nutrients they contain. Some companies create soils that offer a great structure with base nutrients, but allow you to fill in the gaps as you desire.

In hot climates, sandy soil should be mulched to help with water retention and to keep roots from getting too hot.

Climate in your area.

Soil also varies in:

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.

Balcony: This can be a great spot if it gets good light—ideally, it faces south—and will usually get good wind. However, you may need to cover your balcony from peeping neighbors.

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.

Once you have an understanding of the climate in your area, you’ll need to consider a few things before planting your weed.

There are also commercially available soil blends that already contain the proper mix of these types of ingredients.

You also 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.


Big yields.

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.

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 in extreme weather.

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!

Environmentally friendly.

The best way to identify loamy soil is by touching it. How does it feel? Sandy soil should be difficult to compact while clay should compact into a tight ball that won’t crumble. When squeezed, loamy soils should form a loose ball that will hold its structure momentarily before breaking apart in large chunks.

For first-time growers, we recommend avoiding commercial fertilizers like long-release granular fertilizers. These can be used, but you need to have a good understanding of how they work and what your plants need.

While some plants thrive in their native soils, which are usually one of the compositions listed above, cannabis plants are best grown in soil that includes a combination of the three consistencies above—this mixture is known as loam.

Greenhouses also offer growers the ability to harvest more than once per year, if they are equipped with a light deprivation system. These systems allow growers to control the hours of sunlight their plants receive, much like turning lights on and off in an indoor garden, by covering the greenhouse with a black tarp that deprives the plants of sunlight.

Plan to put plants in the ground based on the temperature, season, and light where you live so your cannabis plants have time to finish flowering before cold, rainy weather sets in.

Quality soil is crucial to the success of your crop and one of the few factors that you have control over when growing outdoors.

After the solstice, the available daylight hours decrease, allowing the plant to naturally transition into the flowering period. Cannabis is a short-day plant, meaning it will begin to flower as the nights get longer and the hours of sunlight decrease.

There are also many advantages and disadvantages of using clones. They can often be found at your local dispensary, are from a proven genetic lineage, and typically do well outdoors, making them the perfect choice for inexperienced growers. On the other hand, clones develop a fibrous root system, as opposed to the deep taproots that seeds develop. Fibrous root systems can reduce the plant’s ability to deal with environmental stress and predatory insects.


Greenhouses can be a great middle ground between the complexities of an indoor setup and the uncertainty of growing outdoors. They provide ample protection from the elements and use far fewer resources than an indoor grow. Greenhouses can be more costly than an outdoor garden and require more planning, but they also allow you to extend the growing season considerably.

Plants grown from seeds are typically heartier and more vigorous than clones, as they produce a sturdier taproot that clones are not able to replicate. The vigor that comes from deep roots can be an advantage when dealing with harsh environmental conditions and pest pressures. The disadvantages of growing seeds are the additional attention required to germinate the seeds, the necessity to eliminate any males before they pollinate the females, and the high variability in growth characteristics that results from their genes.

If you live in a climate with exceptionally hot and sunny days, use shade cloth to prevent your plants from overheating. In cold areas, natural enclosures and cement or brick walls can be used to help retain any available heat and keep your plants warm.

In the Northern Hemisphere, cannabis can be planted in early to mid-spring and harvested in mid-fall, depending on the cultivar. In the Southern Hemisphere, the growing season will be reversed with planting in early to mid-fall and harvesting in the middle of spring.

Container gardens can be convenient as plants can be moved around the garden to maximize sunlight or protect them from harsh conditions such as rain, heavy winds, or extreme temperatures.

Cannabis has been cultivated outdoors for thousands of years, but before you go putting a seedling in the ground, it’s best to know how the process works and how to make the most of Mother Nature’s gifts. You should also have some idea of how to handle those unwanted gifts you’d rather return — pests and weeds.

Beneficial insects, fungi, and bacteria can also be used to protect your plants from their parasitic or predatory counterparts. Jumping spiders, ladybugs, and other native, beneficial predatory insects can clear your crop of insects such as aphids and whiteflies. When sourcing beneficial insects, fungi, or bacteria, it’s important to research those which are native to your region.

Avoid clay pots as they can be costly, heavy, and retain heat that could dry out the plant’s soil and roots. Fabric pots are the least expensive and most effective solution, as they allow for ample drainage and plenty of oxygen to get to the roots. Plastic containers are also light and inexpensive but tend to retain more heat than fabric pots. Flowering plants need a container that is at least 5 gallons (18.9 liters) to prevent them from outgrowing their containers and becoming rootbound.

Avoid spraying synthetic insecticides on your cannabis plants as further research is needed to determine the health effects of smoking plants treated with synthetic chemicals. Organic pesticide and insecticide solutions can be effective if used properly. If you can avoid it, it is always best to not spray anything on your plants while they are flowering.

Depending on your location, you may need to plan for rain. In most regions, the rainy season is typically aligned with the end of the flowering stage and the start of the harvesting period, but this may not always be the case. Rain can be detrimental to an outdoor flowering crop so being prepared to cover or move plants can help ensure a successful harvest. If it does rain on your plants, make sure to immediately shake off any excess water, as lingering moisture can lead to the formation of mold and nobody likes moldy weed.


Even if it is legal to grow cannabis outdoors where you live, you should still take some precautions to hide the plants from public view. And it’s often required by law. You can grow your cannabis plants among other plants in your garden to hide them in plain sight. Cannabis can easily grow taller than your average fence, though. Training techniques can help keep your plants shorter. The fewer people who know you are growing cannabis, the better. The ideal situation is to have your grow tucked away on a piece of land where your plants can truly flourish away from prying eyes and nosy neighbors.

Wilting plants and dry soil are a direct sign that plants need water. Droopy leaves along with wet soil are a sign of overwatering. Both are common mistakes and can be avoided with some practice.

Avoid all-in-one fertilizers as they can be too high in nitrogen for the flowering cycle and damage any beneficial microorganisms that may be present in the soil. Instead, choose a line of nutrients created specifically for cannabis, and use its suggested feeding charts to avoid over- or under-feeding. Organic sources of nutrients are best, as they are a great source of beneficial microbes, but they may take longer to break down and become available to the plant. Both types of nutrients can be found in dry, pre-blended powders or liquid emulsions, but can also be made from scratch with the right ingredients. Organic compost tea, which includes nutrient-rich ingredients, like molasses and earthworm casting compost, is a popular homemade brew for cannabis farmers.

Becoming intimately familiar with your local climate and seasons is one of the most important steps in producing high-quality outdoor marijuana. Before you grow, you’ll need to know the ideal temperature your plants require in order to thrive, the best site, optimal timing of planting and harvesting, and the season’s photoperiod — the amount and intensity of light available through the duration of the growing season.

When possible, use natural structures and formations in your garden as windbreaks to prevent excessive stress on your plants that could lead to branches breaking.

To grow cannabis outdoors, the bare minimum required is basic gardening tools, soil, water, and a spot in your backyard that receives ample sunlight.

Timing is key. A short vegetative phase can cause cannabis plants to flower early, while a long vegetative phase can prevent your plants from finishing their flowering cycle if the weather takes a turn for the worse. The Farmer’s Almanac is a reliable source for planning around the seasons and preparing your crop for success.

Greenhouse basics.

Plants grown from seeds are typically heartier and more vigorous than clones, as they produce a sturdier taproot that clones are not able to replicate. Photo by: Gina Coleman/Weedmaps.

If you decide to use seeds, make sure you start them about a month before you would typically start clones to give them time to germinate and adequately develop their taproot.

Determining the optimum location is another important factor that can affect the yield and quality of your plants. Cultivators in the Northern Hemisphere should attempt to place their plants in an area with southern exposure to ensure their plants are getting the most available sunlight. The opposite is true for the Southern Hemisphere.

While cultivars may vary, here are some general rules that will be useful no matter which one you choose.

Pests and wild plants are an inevitable occurrence when cultivating cannabis outdoors. Most issues can be avoided with proper planning. Clearing a buffer area around your plants can go a long way, but your first line of defense is a healthy plant that can defend itself naturally.

During the vegetative stage, water your plants thoroughly, then not again until the top 1 inch (2.54 centimeters) of soil has dried out. This can be every day or every four days, depending on conditions, but the time between watering will become shorter as the plant grows its roots. Container gardens tend to dry out faster than soil beds, so they’ll need to be watered more frequently.

Container gardens can be convenient as they can be moved around the garden to maximize sunlight or protect them from harsh conditions Photo by: Gina Coleman/Weedmaps.

Cannabis requires more nutrients than many of the other plants you may have in your garden. Quality soil contains enough organic nutrients to start the growth cycle, but as your cannabis plant grows and transitions into flowering, it may deplete the available nutrients and require additional fertilizers.

We recommend that cultivators perform extensive research on the strains that are available in their area. Some jurisdictions have more robust strain offerings compared to other jurisdictions. For some cultivators, you will only be able to choose from a handful of strains. Go with the best that you can find, using other cultivators’ experiences with the strain as a guide when applicable. If someone else has successfully cultivated a particular genetic in your area, then chances are you can too!

A standard tomato plant cage goes a long way for bracing cannabis plants. They are affordable and can be found at any home and garden store. Incorporating large bamboo stakes is another good option, as are wooden stakes. For really large plants, using wire fencing is a solid option.

Give strong consideration to creating a ‘super soil’ for use in your garden. The term ‘super soil’ was first coined by legendary cannabis cultivator Subcool. Sadly, Subcool has passed away since first blessing the cultivation community with his soil recipe. He may be gone, yet his legacy will endure forever via his popular recipe.

At the most basic level, cultivating cannabis in a backyard is very similar to other types of gardening activities. If you can successfully cultivate tomatoes, then you will likely be able to cultivate cannabis to some extent. However, that’s not to say that cannabis is easy to grow, at least not in a way that results in a desirable harvest.

Growing cannabis outdoors will inevitably attract bugs and pests. Aphids are a particularly common nuisance when it comes to growing cannabis outdoors. You will want to be proactive and check your plants every day. At the first sign of aphids or other bugs you will want to spray them with soapy water (5 tablespoons of dish soap per 1 gallon of water). You will want to make sure to spray both sides of the leaves to the point that the soapy water is dripping off of the leaves.

Light Deprivation.

If you are using a quality super soil, you shouldn’t have to use nutrients. However, if you are not using super soil you will need to use nutrients to feed your cannabis plants. As with indoor cannabis plants, not all nutrient lines are created equal, and more expensive does not necessarily equate to higher quality. Your best bet is to find someone who has already used a nutrient line that they like and copy their feeding strategy. Over time as you become more familiar with your garden’s needs, you can adjust your nutrient strategy accordingly.

In recent years outdoor cannabis growers have incorporated ‘light deprivation’ techniques into their gardens. Light deprivation involves limiting the amount of sun exposure a cannabis plant receives in order to force it into flowering earlier in the grow season.

If you cannot afford or acquire all of those ingredients, it’s not the end of the world. Include as many as possible, and mix them together. For the best results, place the ingredients on a tarp and mix them around, adding water, then store the “end product” in garbage cans for 6-12 weeks prior to use.

Many rookie outdoor cannabis cultivators make the mistake of planting directly into the soil in their yard. It takes more than just dirt for a cannabis plant to thrive, which is why planting into a container is a much better option.

The type of soil used for an outdoor cannabis garden is paramount, which is a point that Green Flower has touted many times over the years for good reason. If there is one area of the overall garden strategy to avoid cutting corners, whether it involves monetary cost or personal time, it’s the soil. Quality soil will not only help the cannabis plant reach its full potential, but it will also reduce the amount of nutrients that need to be provided to the soil later in the plant’s growth cycle, especially during the flower cycle.

When it comes to cannabis genetics, outdoor gardens are better from a strain selection standpoint compared to indoor grows. Because indoor gardens are typically located in smaller spaces, most cultivators choose indica strains that tend to be shorter. Obviously, with most outdoor gardens height is not an issue and plants can get as tall as they need to be, so sativa strains can be used.

Make sure that your water has a pH level that is as close to 7 as possible. The pH level of many water sources varies by area, even within the same city or county. Always check your pH level prior to watering, and adjust the pH as needed using products that are available in your area.

If preparing super soil is too daunting of a task, using a quality organic soil will work, although you will have to use nutrients during the vegetative and flowering stages to supplement the ingredients of the organic soil. Again, keep in mind that the soil used for growing cannabis outdoors is arguably the most important component to an outdoor garden strategy.

If you can afford it, incorporating a greenhouse into your outdoor garden strategy is a great idea. It doesn’t have to be the fanciest greenhouse in order to help. It can be something that is made from scratch using PVC pipe and clear sheets of plastic. Think of it as building a fort for your garden. For those who can afford it and don’t wish to make their own greenhouse, most home and garden stores carry various sizes of greenhouses.


Light deprivation can be done by simply bringing cannabis plants inside after they have been in the sun for 12 hours, or if you have a greenhouse, placing a dark sheet of plastic or other covering over the greenhouse after 12 hours of exposure to sunlight.

The same is true when it comes to disease. Bud rot and powdery mildew are likely the most common forms of cannabis plant disease when it comes to cultivating cannabis outdoors. Just as with preventing and controlling bug infestations, be proactive when it comes to disease. If you live where rain is common, powdery mildew and mold will also be common, so take steps ahead of time via the use of neem oil or fish oil to help keep diseases away.

For starters, the grower gets to decide what goes into the soil. It’s very tough to know exactly what’s in the soil in someone’s yard or garden area, especially the contents below the topsoil. A yard’s soil could contain all types of materials that might be harmful to cannabis plants.

It’s a lot of upfront cost and effort, however, you shouldn’t have to use any other inputs over the course of the growth cycle. Do not plant a seed or clone directly into super soil. Start with just organic soil, and then transplant into super soil after the root base is strong.

Growing cannabis outdoors is a never-ending educational journey. Even the most experienced cannabis cultivators will be quick to tell you how they are always learning and seeking out cultivation information.

Some strains prefer the sun-grown experience much more than a life under artificial light, and have typical growth cycles that ensure that the plants will be ready to harvest by the end of the outdoor grow season (May to October in most areas). In areas that are farther north from a latitude perspective as measured by the equator, cultivators will want to stick with strains that are ready to harvest quickly because the grow season will be shorter.


The cannabis plant is very dynamic and has particular needs. Successfully growing cannabis outdoors requires knowledge, attention to detail, and a heavy dose of hard work. But it also requires various items to get an outdoor garden started. Those items are discussed below.

Ultimately, the goal is to prevent the plants from receiving light after being in the sun for 12 hours and keeping them in the dark for 12 hours. Light deprivation will help the plants mature faster and speed up the harvest, which is particularly desirable in areas where the grow season is shorter.

Proper bracing of cannabis plants is particularly important for outdoor cannabis cultivation because the plants get so large — especially when growing bigger buds outdoors. For plants that are not going to be cultivated in a greenhouse, that’s especially true because gusts of wind that can easily knock over a cannabis plant, which often proves to be a disastrous event when it occurs.

To learn more about the benefits of super soil check out this What Is Super Soil? guide to the topic. Below is the list of ingredients to make super soil:

Also, containers can be moved as needed, which is necessary to do from time to time. They are also easier when it comes to monitoring moisture. Fiber pots are recommended because they allow the root base to ‘breath’ better compared to plastic pots. The plants will be grown under the sun, so the bigger the container, the better.

At the very least, a greenhouse will help protect the female plants from being knocked over by gusts of wind and/or prevent rain from getting on the plants, which is an especially big concern after the summer solstice has passed and the weather begins to change. At the most, a quality greenhouse can help provide more control over temperature and humidity. A greenhouse can also help with security concerns to some extent, keeping roaming animals out of the garden.

Many novice outdoor growers make the mistake of assuming that ‘cannabis grows like a weed’ — all that someone needs to do is put a cannabis seed in the ground and eventually they will be flush with world-class dried cannabis flower. That is simply not the case.