Choosing The Best Soil For Outdoor Cannabis Cultivation: Soil Types, Recipes, And More

Growing cannabis has become increasingly popular. So much so that almost everyone who uses cannabis is eager to cultivate their plants. 

And, what better way than throwing a seed outdoors and reaping the benefits after a few months, right?

Wrong. 

People who actually grow cannabis will tell you that it’s not so simple. But, if you educate yourself, growing cannabis outdoors is much more rewarding than you expect. 

Outdoor cultivation also offers advantages such as sunlight and ample space for growth; however, one crucial factor that significantly affects the success of your cannabis crop is the choice of soil. The type of soil you choose serves as the foundation for your cannabis plants' health and development.

In this guide, we will understand the importance of choosing the right type of soil to grow cannabis outdoors. If you’re a beginner, understanding the significance of soil will help you grow incredible plants.

Why? Well, growing cannabis is easy only if you provide the right conditions, and one of them is soil, especially if you’re growing outdoors. This means that you must meet specific requirements to ensure vigorous growth, so you can enjoy the rewards later. 

In this article, we will explore aspects related to soil selection, preparation techniques, and maintenance practices so you can make informed decisions. 

Understanding Soil Basics

Soil forms the foundation upon which your cannabis plants either thrive or struggle. Therefore, it is crucial to understand the fundamental aspects of soil science to make decisions about selecting the soil for your outdoor cannabis. 

Types of Soil to Culitvate Cannabis

• Sandy Soil

Sandy soil contains large particles that typically drain quickly. Although it provides good aeration, it doesn’t retain water much water, which means that you should water the plants more frequently to prevent water stress during hot and dry periods. 

• Loamy Soil

On the other hand, loamy soil is often considered ideal for gardening. It’s commonly used for cultivating cannabis due to its balanced mixture of silt, sand, and other particles of clay. This type of soil offers drainage, moisture retention, and aeration, making it suitable for a range of plants. Additionally, loamy soil typically requires maintenance compared to other types of soil.

• Clay soil 

Clay soil is good, but it presents some challenges when it comes to growing cannabis. While it retains moisture well due to its particles, it tends to drain and can become compacted over time. This can lead to issues such as root suffocation and waterlogging. Despite these challenges, it is still possible to cultivate cannabis in clay soil with amendments and care.

Apart from this, soil structure plays a key role in cannabis cultivation as well. Primarily, it refers to how the particles of the soil are organized, so growing in soil with a good structure is important because it influences root health, water absorption, and penetration.

pH Levels

Another important factor is the pH level of the soil which determines its acidity or alkalinity.

Cannabis plants love slightly acidic soils with a pH usually around 6.0 to 7.0. As a student, you may have learned about the pH in your class, but as a grower, it’s incredibly important. This is because the pH influences a lot of things in the cannabis plant. For example, if the pH goes below 6 or above 7, the plant will not be able to access certain nutrients, making it weak and prone to deficiencies. Thus, remember to measure and adjust the pH of your soil to create a perfect environment for growth. You should do this even when you're adding nutrients. 

But, how do you determine the pH of your soil? It’s simple — use a pH meter. Or, you can get pH testing kits from gardening stores. If you want to take it a step further, you can take soil samples from the area where you want to cultivate cannabis and get the pH checked in a lab. 

After testing, if you find that the soil is very acidic or below the range required, you just have to increase its pH. You can do this by adding wood ash or lime (calcium carbonate) or wood ash. Make sure you follow the instructions provided by the manufacturer.

Similarly, you can decrease the pH of the soil if it’s above the range or is alkaline. Use gypsum, sulfur, or aluminum sulfate to do so. 

Remember that it’s important to maintain a proper pH range in the soil to encourage good growth and prevent deficiencies that can reduce the yields. 

Nutrient Content

Good soil will already contain nutrients that are essential for plant growth. Cannabis plants, like most plants, need macronutrients like nitrogen, phosphorus, and potassium, and micronutrients like iron, zinc, copper, etc. Of course, there are many other micronutrients that the plants need, but the soil must contain these nutrients at adequate levels as they are vital for the plants to grow and produce buds. Do some research and understand more about the types of nutrients necessary for cannabis as it’s important to grow the plants in a balanced soil mix that contains all nutrients. 

Organic Matter

The organic matter is nothing but animal and plant matter that has decomposed. Compost and rotted manure are great for adding organic matter to your soil. If you’re going to use manure, make sure it’s old as you don’t want to introduce fresh manure into your soil. Fresh manure will spread diseases, and you seriously don't want that. 

Organic matter enhances the structure of the soil, its ability to retain water, and its capacity to hold onto nutrients. Organic matter also promotes the growth of microorganisms that improve the root health. There are various options to add organic matter, and you’ll be spoiled for choices, so simply choose a few and add them to your soil. In the later sections, we will go over a recipe that includes various types of organic matter you can add to the soil.  

Drainage

Good soil must have the ability to drain well to prevent waterlogging. Cannabis plants hate getting their roots waterlogged, which can lead to root rot and other problems. So, whether you’re making your own soil or purchasing some, make sure it drains properly. Also, remember that not only hydroponic but also plants growing in soil need oxygen to grow well. Good soil that drains well will provide ample oxygen to the roots and ensure they are happy, which, in turn, will make you happy!

Now that you understand the basic concepts of soil, you’ll hopefully be able to make better decisions while selecting the right soil for your outdoor cannabis garden. Every factor mentioned above is important, so pay attention to all of them. 

Should You Grow Outdoor Cannabis Plants in Containers or in the Ground?

You can plant cannabis either in the ground or in containers — the choice is yours. However, you have to have to consider various factors such as your climate conditions, goals, space available, and the control you want to have over the growing operation. Let’s take a look at the pros and cons of each decision:

Planting in Containers

Pros

1. Portability

One major advantage of using containers is that you can move your cannabis plants around. So, if the weather is really hot, you can move your plants inside or to any location with some shade. Similarly, you can take the plants indoors when the weather is very cold. Some growers prefer planting in containers as they can “chase the sun” to ensure the plants have ample light throughout the day. Also, remember that it offers security and privacy. 

2. Pests and Disease Management

You can manage pests and diseases a bit more easily if your plants are in containers as your plants will be elevated. You will avoid the risk of pests and diseases associated with soil. This is not to say that your plants will be completely immune to pests and diseases just because you’re growing them in containers. The risk is reduced to a good extent, but you’ll still have to monitor your plants and take preventative measures. 

3. Control

Some growers love growing in containers as they offer more control over the plants. For example, you can customize your soil mix according to the type of strain you’ve chosen, move plants easily, and do a lot more. This type of control allows you to grow plants that produce premium buds. 

4. Space

If you grow your cannabis plants in containers, you can place them pretty much anywhere, as long as they get ample light. So, even if you don't have a lot of space, you can still grow cannabis outdoors. For example, growing cannabis plants in containers on your balcony is a great idea if you don’t want the plants in the front yard. 

5. Less Effort

Planting your cannabis plants in pots will take considerably less effort than preparing the ground to plant the seeds or seedlings. Many people assume that growing plants directly in the ground is as easy as throwing a seed and letting the plant do all the work. Unfortunately, you’ll be sadly mistaken as growing in the ground will take more elbow grease compared to just making your own soil mix. 

Cons

1. Less Root Space

Compared to plants grown in the ground, plants bound by containers will have less space and won’t allow the roots to branch out easily. If you use small containers, it can restrict their size and overall yield ultimately as they are unable to develop large root systems. Also, planting a strain with the potential to grow large in small containers will make them root-bound, where the roots start encircling the inside of the container. This can result in stunted growth and reduce the yields as well. 

2. Maintenance

Adding to the previous point, since there’s less root space, you’ll have to monitor plants growing in containers more closely, especially when it comes to watering and feeding nutrients. The growing medium is bound within the container, so you should keep an eye on the moisture at all times. 

3. Cost

Growing in containers will be more expensive than growing in the ground as you’ll have to invest in containers, soil, etc. Even if you make your own soil, you’ll have to invest in extra amendments; however, it will get easier in the long run as you can reuse most equipment and even sterilize soil to reuse it again. 

Planting in the Ground

Pros

1. Natural Environment

Planting cannabis directly in the ground has its advantages as it allows your plants to grow in their natural environment. However, the soil should be suitable for cannabis. If you take care of this fundamental factor, everything else will fall into place. 

2. Nutrient Uptake

Another benefit of planting in the ground is that your precious plants can access all soil nutrients, eventually leading to higher yields. 

3. Size

The most important advantage is that the plants grow huge as nothing is binding them. Naturally, the yields will be larger than plants growing in containers, thanks to an extensive root system. 

4. Watering

You’ll notice that you won’t have to water these plants as much as plants growing in containers because their larger soil volume helps retain moisture efficiently, reducing the chances of the soil drying up.

Cons

1. Challenges with Pests and Diseases

Although natural soil offers some advantages, it can make it a bit more challenging to deal with pests and diseases. Plus, since the plants grow large, you will have to plan and focus on preventive measures to ensure pests don't bother your plants. 

2. Less Control

The flip side of growing in the ground is that you have less control over the plants. This means that you won’t be able to customize the soil according to your plant’s specific needs. If you reside in a location where the soil is unsuitable for growing plants, you will have to add extra nutrients to the soil. If the soil is fertile, cannabis plants adapt pretty quickly. 

As you can see, both types of cultivation have their pros and cons, so you should make a decision based on your needs, space, and your local climate. 

Purchase Soil Or Make Your Own?

If you choose to grow cannabis in containers outdoors, you’ll next to have decide whether you want to make your own or buy a premade mix. Let’s understand the pros and cons of each so you can make a better decision. 

Creating Your Soil Mix

Pros

1. Customization

Every serious grower wants to customize his own soil so he has complete control over its composition. This is a great advantage because it allows you to tailor the soil precisely to meet your strain’s requirements and also adjust pH and other factors based on what your plants need.

2. Cost Effective

You can save money by making your own soil since you can use free organic materials. Of course, this doesn’t mean that you can simply throw organic waste into the soil — you have to let it decompose first and turn it into compost, so this does take some planning, although it’s certainly cost-effective. In addition, you will have to purchase some amendments if you’re going to rely only on compost, so you’ll have to spend some money, but it’s cheaper than buying pre-made soil mixes. At the same time, you will also be environmentally conscious as you’re recycling stuff to grow something you truly love — a win-win!

3. Learning Experience

Crafting your soil mix helps you understand the science behind the soil and its connection to cannabis cultivation. You will acquire hands-on knowledge of soil structure and the significance of balance in your growing medium.

Cons

1. Labor and Time

Preparing DIY soil requires labor and effort. You need to spend a lot of time sourcing ingredients, mixing them in the correct proportions, and then allowing the mixture to properly mature. It becomes even more challenging if you’re planning to grow multiple plants. 

2. Consistency

It can be difficult to achieve consistent results, especially if you’re a beginner. The nutrient balance and soil pH can vary from one batch to another, so plant growth can be unpredictable. It can take some trial and error to find the mix that meets your plant's needs. However, if you keep up and invest your time and effort, it will be worth it in the end. 

Purchasing a Pre-made Soil Mix

Alternatively, you can buy soil mixes. Here are the advantages:

Pros

1. Convenience

Would you rather cook an extravagant dinner or purchase a feast from your favorite restaurant? Purchasing pre-made soil mixes are something similar. It is convenient as you save time and effort compared to making your mix where you have to measure and monitor everything. This makes it great for growers who don’t have time and prefer a simple approach.

2. Consistency

Unlike DIY soil mixes or super soil you make at home, pre-made soil mixes offer consistency. Of course, it also depends on the environment you grow. For example, you can’t expect consistent results if you use inferior lighting or if there’s a drastic difference in temperature between two plants even if you're using the same mix. However, pre-made soil mixes are typically consistent in terms of texture, nutrients, and pH levels, which kinda makes it easier for you to grow plants.

3. Beginner Friendly

Pre-made mixes are great for you if you’re a beginner with less knowledge about soil science. All you need to do is purchase the soil mix and get growing!

4. Brand Reputation

Established brands are known for their quality, so you can rest assured that these premixes are designed keeping plant growth in mind. 

Cons

1. Cost

Making your own DIY soil is cheap but purchasing premade soil mixes is expensive. The cost simply goes up if you plan to grow many plants. However, you can reuse them in the future if you sterilize them properly, although you will have to add fresh nutrients again. 

2. Customization

You can’t customize a premade mix according to your plant’s requirements. Although many growers don’t mind this disadvantage, growers who love the flexibility of customizing their soil mix may not find this appealing. 

On a side note, if you’re environmentally conscious, ensure you purchase reputed brands that disclose all the ingredients they use and keep synthetic ingredients to a minimum. 

To conclude, you can grow amazing cannabis plants and get beautiful yields whether you grow them in pre-made soil mixes or in your own super soil you made at home. At the end of the day, it depends on other factors like lighting and the environmental conditions you provide too. 

Many growers grow in a combination by using a base mix as a foundation and then adjusting it according to their cannabis plants' specific needs. If you’re very budget-conscious (as cannabis cultivation demands a significant investment at the beginning) you can try making your own soil. However, if you choose not to break your head with the intricacies of soil science, simply purchase some commerical soil mix from a reputed brand and be done with it. 

How to Make Super Soil to Grow Cannabis Plants Outdoors?

If you’ve ever tried to grow cannabis outdoors or even indoors, you’ve probably heard of super soil. Many growers start with pre-made mixes but once they realize that the cost becomes significant over time, they turn to other affordable methods of growing cannabis, and making your own DIY super soil is one of them. 

Super soil is nothing but soil that contains nutrients and other rich organic matter. A grower named SubCool created the recipe, but it has been modified over the years by various growers. 

Here’s a basic guide to making DIY super soil. You can alter this, depending on how many plants you want to grow. 

Ingredients

1. 8 bags of organic compost or soil containing coco peat and mycorrhizae to take care of the basic needs of your plant. If your compost doesn’t contain coco fiber, you can add it here. Add 4 bags of coco and 4 bags of compost to make it a total of 8 bags. Similarly, add some mycorrhizae fungi if your compost doesn’t contain them. Coco peat helps your plants retain moisture but also can drain quickly to prevent waterlogging. 
2. 25 to 50 lbs (10 to 50 kgs) of worm castings that are rich in beneficial microbes and other nutrients to provide nourishment to your plants. They act as slow-release fertilizers. 
3. 5 lbs or 2.25 kgs of blood meal as it’s super rich in nitrogen that helps the plants develop lush leaves and strong stems. You can use fish meal as an alternative. 
4. 5 lbs or 2.25 kgs of bat guano, which contains basic nutrients like nitrogen, phosphorus, and potassium for plant development.
5. 5 lbs or 2.25 kgs of bone meal as it contains lots of calcium and phosphorus.
6. 5 lbs or 2.25 kgs of kelp meal as they include trace minerals and compounds that enhance the growth of your plants. 
7. 3/4th to 1 cup of Epsom salt for magnesium and sulfur. 
8. 1/2 cup of dolomite lime to adjust the pH and provide magnesium and calcium to maintain plant growth. 
9. 3 lbs or 1.3 kgs of rock phosphate for phosphorus. 
10. 1/2 cup of azomite for micronutrients.
11. 2-3 tablespoons of seaweed solution or humic acid for soil conditioning and trace nutrients. 

Super Soil Recipe

Making Super Soil 

1. Prepare workspace

First, select an area that’s large enough to make the mix. Spread a tarp so it’s easier to clean.

2. Make the base mix

Now, combine some coco peat and compost on the tarp. You can use a container if you like; however, the container won’t be able to hold so much soil, so it’s best to do it on a plastic sheet. If your compost already has some coco peat mixed in, just let it be. This mix serves as the base or foundation for your super soil. Remember that you need to have equal amounts of compost and coco coir. 

3. Add the amendments one by one

Add bat guano, worm castings, bone meal, blood meal, fish meal, kelp meal, rock phosphate, and azomite to the soil mix. 

4. Mix everything thoroughly

Mix all the nutritional amendments into the soil and combine everything for even distribution. Ensure the soil is free from clumps. Use a rake to do this. 

5. Aging

Let the soil mix rest for about 3-4 weeks so it matures. Fresh mix can be too hot for the plants and burn them. You can cover the soil with a tarp or place it in a container and cover it. This aging process will break down the ingredients and make them easily accessible to your cannabis plants.

6. Planting

Once the soil is aged, your super soil is ready and you can use it to grow your plants. However, this super soil is too rich in nutrients and your small seedlings may not be able to take it. Therefore, fill only a third of your pot with the super soil and fill the remaining with a mix of compost and coco peat (base mix) so the plants don't get burned. 

7. Monitoring and Feeding

Now, all you need to do is monitor your plants as they grow. Although super soil is good enough for your plants from start to finish, you can add some amendments like liquid fertilizers to ensure the plants don’t lack anything. This is optional. 

And, that’s it — you’re done. Remember to let the soil mature so there’s a chance for the matter to break down. If you skip this process, the plants won’t benefit much from the soil. 

How to Prepare the Ground to Grow Cannabis Outdoors?

If you’re lucky to have ample space to grow cannabis outdoors and don’t have to worry about prying eyes, you can easily grow cannabis in the ground. This is the best option as your plants will have the ability to develop extensive root systems. The yields will also be much more than growing in containers. 

Here’s a step-by-step process to help you do the same. 

1. Select an Ideal Location

Choose a spot that gets plenty of sunlight. At least 6-8 hours is ideal. Also, ensure there’s enough airflow to prevent the growth of mold and mildew. If possible, choose a location that’s directly not accessible to others. 

2. Prepare the Area

Remove any existing plants, weeds, or debris from the area to make it easier to plant your cannabis plants. The area should be clean and devoid of grass to create a planting bed.

3. Improve Soil Quality

Test the soil's pH levels to determine whether it’s suitable to grow cannabis. You can get this done in a lab or use a pH meter. Increase or decrease the pH to make sure it’s within 6-7. Add organic matter like compost or rotted manure to enhance its nutrient content and structure.

4. Level and Loosen the Soil

Use a garden rake to level the ground and break up any clumps of soil.

5. Create Raised Beds (optional)

If you don’t want to plant your cannabis plants directly in the soil, you can create raised beds. This will also improve drainage in areas with poor soil quality or heavy rainfall.

6. Install Irrigation System (optional)

If you don’t have the time to water manually, you can install irrigation systems such as hoses or drip irrigation for watering.

7. Plant Companion Plants (optional)

To prevent pests, you can plant other companion plants like herbs that discourage pests to a certain extent. 

8. Soil Settling

Allow the soil to settle for a week or so before planting so soil amendments can integrate properly. 

9. Timing and Acclimatization

Choose the time to plant based on the climate in your area. Cannabis plants are usually sensitive to frost, so you should plan ahead. If you're starting with seedlings or clones, do not expose them immediately to sunlight; instead, do it gradually by planting the seedlings in a separate container so they don’t undergo any stress. 

10. Install Support (optional)

Some strains grow so huge that they topple down. If you’re growing a strain that can grow large, install stakes or other supports to help them grow upright and support their weight. You can even use a large tomato cage to form a base for the plants. 

11. Mulching and Weed Control

Apply some mulch on the base of the plants to help them retain moisture, especially if the weather is very hot. Mulching will also help reduce weed. 

12. Make a Feeding and Maintenance Schedule

Keep an eye on the requirements of your cannabis plants so they don’t lack anything. Add fertilizers or amendments when necessary, but don’t overdo it. 

13. Harvest 

Read about when you can harvest your specific strain. This can help you plan ahead and prepare for important stuff like drying and curing. 

That’s it! Do all this and you will be able to enjoy your buds in no time!

Summary: Choosing The Best Soil For Outdoor Cannabis Cultivation: Soil Types, Recipes, And More

So, there you have it. If you want to grow cannabis outdoors, the most important thing you need to take care of is the soil. You can grow either in pots or in the ground, but the quality of the soil matters a great deal. 

Also, make sure you check the pH of the soil and the nutrients you add so there’s no scope for any deficiencies. Cannabis plants prefer slightly acidic soil that ranges from 6 to 7 and going above or below this range can cause nutrient deficiencies. 

Remember that it’s easier to buy pre-made soil mixes but you can save some money with super soil. This doesn’t mean that making super soil is free. As you read above, super soil also takes quite a lot of ingredients for optimal plant growth; however, they can be cheaper than pre-made mixes and give you the option to add more nutrients suited for cannabis.