Cannabis plants can be grown in the ground, giving you cheaper and bigger yields than growing indoors or using hydroponic systems alone.
The first thing that’s important to know about growing cannabis with soil is that there are several different types of soil mediums out there. The three most common are:
· Regular garden soil
· Soilless potting mix
· Composted super soil
Each have their own pros and cons, but for the sake of simplicity we will only be discussing growing with a soilless potting mix. This is because it can mimic a hydroponic system, but at a fraction of the cost.
Growing with soil is best started indoors in order to control your environment and speed up the growing process. If you are interested in starting seeds, make sure you read our ” How to Start Your Marijuana Seeds Indoors Guide “.
Soilless potting mix is available at most garden supply stores, however, we suggest buying it online. This way you can ensure that the soil has been sterilized and is safe to grow your plants in. We recommend using Fox Farms Ocean Forest Soil mixed with another organic medium like perlite or coco coir.
Once you have your soil, fill your chosen containers (make sure they are at least 3 gallons) with your soil mix and wet the soil until its all moist. Use a PH meter to check the pH of the soil and adjust it if needed before planting your seeds.
Here is a quick guide on how deep you should plant your seeds:
· Seeds planted 1/4″ to 3/4″ deep in regular soil
· Seeds planted 1/2″ to 3/4″ deep in a soilless mix
Make sure that you keep the soil moist until your plants have germinated. After they have sprouted, make sure to wait until the cotyledon leaves dry out before watering them again. Keep them growing indoors until the end of their flowering cycle or until you are ready to put them outside.
We suggest waiting until the end of the 2nd week, but this is when things can vary depending on your strain. Make sure not to overwater your plants in soil after they have grown too large because it will cause root rot and possible death.
There are many different ways to prepare your soil to make it ready for growing cannabis. Some growers like to add composted manure, while others prefer worm castings. If you are looking for a simple guideline to follow when adding nutrients, try following this easy step by step guide:
· Mix in 1/4 cup of bone meal per every gallon of soil
· Mix in 1/4 cup of blood meal per every gallon of soil
· Mix in 1/2 cup of Epsom salts for every gallon of soil
After following these guidelines you can mix in your desired amendments, like alfalfa meal, kelp meal or guano. Make sure to mix well until everything is broken down thoroughly.
Proper pH for growing cannabis in soil
The pH of the root zone affects nutrient availability, being either available or unavailable to the plant. A lower pH makes nutrients less available, while a higher one makes them more available. The optimum range for most minerals is between 5.5 and 6.5.
Most nutrients need a specific pH level in order to be absorbed by the roots, for example:
· The optimal pH level for phosphorus is between 5.0 and 7.0
· Iron needs a pH of around 7 in order to be available to the plant
When you test your soil pH, make sure to test several soil samples in different places because the pH level can vary between different parts of your growing space. If you are looking for a general guideline on how to adjust the pH of your soil to get it ready for cannabis growth, use this chart:
· 6.0-7.0 = Happy roots, perfect for growing cannabis
· 5.0 = Optimal pH but can still grow cannabis, although some nutrients will be unavailable
· 4.5-5.0 = Too acidic and not suitable for growing cannabis if your choose to use regular soil (use a soilless potting mix instead)
It’s important to remember that the nutritional value of your buds is directly related to how well you take care of your plants during the vegetative stage. That being said, you should learn how to feed your cannabis plants properly in order to get bigger and better yields.We have a great article explaining everything you need to know about feeding marijuana plants . Make sure to check it out if you haven’t already.
There are many different amendments that can be added to soil, but the most popular choices are peat moss, perlite and vermiculite. Many growers choose to use a combination of these three during their grow.
As stated before, composted manure is also a great amendment for your soil mix, since it adds nutrients and helps aerate the soil.
Small amendments that you can also add to your soil mix are:
· Crushed oyster shells – Adds calcium and magnesium which help prevent blossom end rot in later stages of flowering , as well as a great pH buffer for making sure your soil stays at the right pH levels.
· Crushed egg shells – Will add calcium slowly over time, which is great for plants that need a lot of calcium during the vegetative stage. This will not burn your plants, so you can crush up whole egg shells and use them in your soil mix without worrying about it hurting your plants.
· Lime – Will raise your soil pH, so you should test your soil before adding it.
When growing in soil, watering is probably one of the most important aspects that you will need to learn how to do correctly. This is especially true during the vegative stage of your grow.
Stay tuned for Part 2!