When cultivating marijuana indoors, one of the first (and most crucial) choices you’ll have to make is deciding what type of soil to use.
But if searching for the right soil to use for your next harvest sounds too daunting, then don't worry! This post was written with people like you in mind.
Most organic soil mixes are usually packed with a wide variety of. However, it’s important to keep in mind that the nutrients in soil mixes never last forever and need to be added manually after every few weeks.
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3 Top Soils for growing cannabis
1. [Best Overall] Fox Farm Ocean Forest
One of the biggest plus points of this soil mix is that it’s already set to the ideal pH needed for growing marijuana plants.
4.9/5
2. [Best For The Money] FoxFarm’s Happy Frog
It’s 100% organic, pH adjusted, possesses beneficial microbes, has a decent coverage area, and is ready to use with all the key nutrients needed to ensure your plants thrive
4.8/5
3. [Best For for Hobby Growers] Purple Cow IndiCanja
This natural organic potting canabis soil comes with all the necessary minerals and nutrients needed to kickstart your plant’s growth journey.
4.7/5
In this post, we'll discuss the best types of soils for an indoor setup and some of the most important factors to consider when choosing one.
Additionally, we'll list a few of our favorite soils for marijuana, so you can get bountiful yields every time!
By the way, if you’re confused between using soil and hydroponics to grow your plants, here’s our guide on the difference between soil and hydroponic marijuana.
What makes for good soil for growing cannabis?
When shopping for soils, you need to consider a few important properties of the canabis soil such as its pH, texture, drainage, water balance, and nutrient profile. Let’s discuss them in detail.
pH
pH refers to how acidic or basic a solution is. Generally, marijuana thrives in a good cannabis soil pH of around 6 to 7.
Slight deviations from this range don’t usually cause much damage. However, if it goes significantly beyond this range, you’re likely going to encounter dead plants, lower produce, and stunted growth.
Texture
The best soil for cannabis to grow indoors includes an optimal mix of sand, silt, and clay soil (loamy soil). Ideally, this mixture should contain roughly 40% of clay, 20% sand, and 40% silt.
Using a medium with a light soil texture like loamy cannabis soil helps with root growth and ensures adequate amounts of oxygen is always available for your plant.
Drainage
Good quality soils for marijuana always have proper drainage ability. When watered, soils should not hold water to the extent that it pools up to the top for more than a couple of seconds.
Bad draining soils cause plants to become more susceptible to root mold and rot. Here’s how you can get rid of mold on weed.
Water retention
Although you always want to use cannabis soil with proper drainage, you never want the water to completely flush through the soil without allowing the roots to absorb vital nutrients and water.
Essentially, water retention means the ability of the soil to hold water. The best types of soils for indoor growing always have well-balanced water retention and drainage properties.
An easy way to tell if a soil has good water retention properties is to check if it holds onto water without getting too “muddy” — always remember, wet soil is good but dirt-batter isn’t!
Nutrients
Cannabis plants need more than just water and light — they also need nutrients to survive! That’s why it’s essential to ensure there are plenty of nutrients present in their soil at all times.
Otherwise your plants may turn into hermies, which are useless. It’s important to spot hermie plants early on so you don’t waste your efforts on them.
Well-balanced soils often contain a number of rich minerals, organic elements, and helpful microorganisms. Common ingredients used include coco coir, bat guano, peat moss, perlite, worm castings, and mycorrhizae. All of these ingredients help keep your marijuana plant well-fed and boost the soil quality.
essential nutrientsOur favorite soils for growing cannabis indoors
Now that you know what factors to consider when shopping for soil, it’s time to present our list of favorites.
Here are the top 4 soils available in the market today for growing cannabis indoors.
When it comes to germinating cannabis plants indoors, FoxFarm’s Ocean Forest soil mix is one of the best options available out there.
One of the biggest plus points of this soil mix is that it’s already set to the ideal pH needed for growing marijuana plants.
And even though it’s not 100% organic, it’s still jam-packed with a number of healthy nutrients.
Additionally, it’s not as expensive as other alternatives in this list and is great for germinating new plants.
Pros
Cons
This soil mix is one of the highest-rated options available on Amazon, and for good reason too!
It’s 100% organic, pH adjusted, possesses beneficial microbes, has a decent coverage area, and is ready to use with all the key nutrients needed to ensure your plants thrive!
However, due to its premium quality, the price might prove to be a bit steep for some.
Pros
Cons
This natural organic potting soil comes with all the necessary minerals and nutrients needed to kickstart your plant’s growth journey. It’s ready-to-use, clean, good for all stages of plant growth, and is the soil mix of choice for many professional cannabis growers.
However, it should be noted that some users have complained about bags being infested by fungus gnats.
Pros
Cons
The last entry in this list is another popular and highly rated soil that’s available at a very fair price.
Mother Earth’s Terracraft Soil is an all-purpose soil that’s developed and designed by experts to help your marijuana plants thrive all the way from their seeding phase to harvest.
This soil mix includes a number of beneficial ingredients such as:
- Perlite
- Earthworm castings
- Peat moss
- Yucca
It helps create the perfect conditions for your cannabis plants and it’s a great option for growing both outdoors and indoors.
Pros
Cons
FAQs
1. What type of soil is best for growing marijuana?
Soil that is high in organic matter is best for growing marijuana. The organic matter helps to retain moisture and nutrients, and provides a good environment for microbial activity. Soil that is high in clay or sand is not ideal, because it does not retain moisture or nutrients well.
2. What are the different types of soil available for growing marijuana indoors?
There are a few different types of soil that can be used for growing marijuana indoors. One popular option is organic soil, which is made from natural materials like composted animal manure and peat moss. Another option is soilless mix, which is a blend of coco coir, perlite, and vermiculite. This type of soil is often used for hydroponic growing systems.
3. How do I choose the right soil for growing marijuana indoors?
There are a few things to consider when choosing soil for growing marijuana indoors. The first is the type of soil. There are many different types of soil, but some are better suited for growing marijuana than others. Soil that is rich in organic matter and has a good pH balance is ideal.
The next thing to consider is the size of the pot. The pot should be at least twice the size of the root ball of the plant.
4. What kind of soil should I avoid when growing marijuana?
Soil that is high in nitrogen should be avoided when growing marijuana, as it can lead to excessive vegetative growth and low yields. Soil that is low in pH or high in salts should also be avoided, as it can damage the plants.
5. What are some common problems with growing marijuana indoors?
One common problem with growing marijuana indoors is that the plants can become too tall and spindly, making them difficult to grow and harvest. Another issue is that the plants can be susceptible to pests and diseases, which can damage or kill them. Additionally, indoor growers may have difficulty creating the right conditions for their plants to thrive, such as the correct temperature and humidity levels.
🌿 Join my "growing" community
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from seeds to smoke!
— Morgan, 420GreenThumb 🌱