Cannabis Learning Center: Grow Media

Cannabis Grow Media

Grow media plays a vital role in indoor cannabis cultivation. It serves as a substrate to support the roots, provide essential nutrients, retain moisture, and ensure proper aeration. There are various types of grow media available, including soil, coco coir, perlite, vermiculite, and rockwool. Each medium has its unique characteristics, such as water retention, drainage, and nutrient-holding capacity. Understanding the properties of different grow media allows cultivators to choose the most suitable option based on their specific growing needs and preferences. Whether you opt for soil-based or soilless mediums like coco coir or rockwool, selecting the right grow media is crucial for creating an optimal root environment and facilitating healthy plant growth in your indoor cannabis garden.


Grow Media for Soil Grow

Grow Media is simply the material your plants' roots will occupy. You can find many different types of Grow Media 
Soil, rockwool, clay pebbles, peat and coco coir are all examples of grow media. Your choice of grow media will dictate how you water, fertilize and train your plants.
The best grow media is subjective. Whichever is going to fit your style and your equipment will be the best for you. But always keep an eye out for the quality of what you're purchasing. Make sure you are sourcing authentic products from reutable retailers to ensure you receive clean, pest free media. Browse our selection of Grow Media Here.
Soil is a plant's natural grow media. While humans are clever and have created other mediums to grow plants, it's hard to argue against good old fashioned soil from mother nature. A rich soil will have most if not all of the nutrients your plant needs. Soil use also allows you to add amendments not available to other systems. If you want to fertilize with soil, you still can. Soil is also great for beginners since it's much more forgiving than a hydroponics system and lets you focus on learning other important aspects of growing cannabis first before making the jump into more complexity. Check out our Soil Options Here.
You may often come across coco coir when reading whats in your soil blends. Coco coir is the ground or shredded husks of the coconut. Its a clean, inert media that holds water well without retaining excess within the spaces in the soil. This allows better root oxygenation and therfore, root development. Coco coir is often mixed into other fortified soils and can be found in many professional blends both indoor and outdoor.
Perlite is a porous mineral product that is fantastic for retaining moisture without stagnation and can help keep air available to the roots of your plant. You may have seen perlite in potting soil as little white pebbles. You can buy soil with perlite added, or grab a bag of perlite and add your own to your secret blends! 
Some of the most common issues that arise in soil applications are:


Nutrient depletion - where the soil you're using no longer contains enough nutrients for the plant. This can happen when reusing soil over a period of time. Chemical fertilizers can reintroduce vital nutrients back into the soil and can get you back on track. 


Improper drainage- If your soil is too dense, or you don't have adequate drainage in your pots, root rot or mold growth can happen quick. Always make sure your pots have ample drainage to prevent issues. Luckily, our cloth pots provide ample drainage.


Clay- If you are using just the soil in your yard or are growing outside, make sure that the clay content is low. Clay can disrupt your plants' ability to absorb nutrients by cloging the roots and sealing them from taking up nutrient rich water. 


Over/under-watering- Sometimes soil can look dry on the surface, but be nice and moist underneath. If your soil is dry past the first knuckle of your finger, its time to water. Consider investing in a Soil Moisture Meter for the most accurate results.


Salt build-up- If you are using fertilizer over a long period of time, salts can eventually build up in your soil and high concentrations of salt pull water from your plant. No water in a plant = death. rinsing or flushing these salts out of your soil with clean fresh water or a Flushing product is a must! 


Pests- Soil creates a perfect environment for pests and other unwanted critters to live. by adding diatomaceous earth to your blend you can keep most things out of your soil. Mycorrhizae and other microbe amendments can keep unwated fungi and bacteria out of your soil as well.


You absolutely can! Many growers use small rockwool cubes mixed into their soil for water retention purposes. Many growers will start clones in rockwool and then simply plant the rockwool in soil for the plant to grow into. We advise keeping any particulate grow media like soil, out of your hydroponic system.
Drainage helps keep your soil from becoming waterlogged, in which case your plants won't be able to absorb oxygen and will die. It also allows you to flush your soil to prevent nutrient lockout or salt buildup. If you want to be proactive about removing salt from your soil, Foxfarm Sledgehammer is a fantastic product for flushing your soil.
pH test meters are available to make sure your soil stays at the optimal pH for minerals to disolve and be absorbed. pH up and down are also available in case you need to supplement your water and soil. GrōHaus offers both a test strip kit and an electronic meter to optimize your pH to a healthy 5.8-6.2.
Any new bag of quality soil will contain all the nutrients the plant needs from seedling to harvest. Your plants will produce quality flower in relation to the quality of your soil. Many like to go above that and supplement their soil to acheive their strains maximum potential. To fertilize with soil, simply follow the manufacturers instructions on mixing and watering. 

Most feeding schedules tend to be every other watering, but its imperative that you read the instructions set by the manufacturer, at least at first until you get more experienced with nutrient feeding. What's important is to keep track of your feeding and watering routine. One great way to do this is by keeping a garden journal. Write down everything you do so that you can go back and reference things like feeding or pruning. This practice can help you see what works and what doesn't and can prevent overfeeding or under-watering. 

A soil amendment is anything you add to boost a feature of your soil. Perlite, mycorrhizae, diatomaceous earth, and worm castings are all soil amendments. We recommend FoxFarms' Microbe Brew for lush and flourishing plant growth


Grow Media for Hydroponics

Hydroponics is the science of growing plants with nutrient laden water instead of soil. There are many different versions and types of hydroponic setups to choose from.
There are many mediums that work with hydroponic systems. Depending on the system you choose, you can use rockwool, clay pebbles, substrate mats. Some systems don't even use a medium, and roots are grown submerged in water or in nutrient mist! Check out our Hydroponic substrate section here.
Hydroponic systems allow you to fine tune your crop, resulting in large yields, high quality, and faster growth. Another benefit is the automation that is possible. A carefully calibrated and monitored hydroponic system can be a time efficient solution.
The main types of hydroponics on the market today, Ebb & Flow, Deep water Culture, and NFT or Nutrient Film Technique each have their pros and cons. Let's explore further:


Ebb & Flow- Ebb & Flow or "flood and drain" hydroponic setups involve flooding a tray containing plants with nutrient rich water from a central reservoir. After the substrate the plants are using takes up enough, the water drains back into the reservoir. This allows the roots to sit in open air, triggering explosive root and plant growth. Plants tend to grow fast and lush with this setup. You can find an Ebb & Flow kit here. 


Deep Water Culture: Deep water culture, often referred to as DWC, is a hydroponics style in which the roots of the plant are submerged in a hyper-aerated water/nutrient solution. With this system, roots are constantly receiving water, oxygen, and nutrients, making them grow quickly and produce large yields. DWC kits are typically inexpensive, easy to set up, and good for beginners due to their lack of needing water circulation pumps and extra reservoirs. You can browse our selection of DWC kits here.


Nutrient Film Technique: NFT (Nutrient Film Technique) hydroponics is a method where a thin film of nutrient solution continuously flows over plant roots, providing essential nutrients directly to them. In this technique, plants are typically grown in channels or gullies with a slight slope, allowing the nutrient solution to flow over the roots and then return to the reservoir for recirculation. NFT hydroponics is known for its efficient use of water and nutrients, promoting fast and healthy plant growth while minimizing waste. The Super Flow 20 Site Kit from Superponics is a great product to get started in the world of hydroponics.

Hydroponic growing presents several potential risks and challenges, including the risk of power outages leading to system failure, susceptibility to waterborne diseases due to the plants being grown in water instead of soil, and the possibility of water leaks causing damage to the setup and surrounding areas. 

Additionally, maintaining proper nutrient levels in the water solution is crucial to prevent nutrient deficiencies or toxicities in the plants, and any imbalance could lead to stunted growth or plant death. Furthermore, the initial setup costs and ongoing maintenance expenses can be significant, posing financial challenges.

We recommend any of the following systems for beginners looking to try their hand at Hydroponics:
The short answer is, No. There will always be a need for a gardener to monitor the overall health of the garden. Water levels need to be checked and maintained, nutrient levels will need to be balanced, and plants will need to be inspected for signs of root issues or pests. That being said, Hydroponic systems can drastically save you time and energy by providing automation that needs to be supervised, rather than work that needs to be done. 
The typical hydroponic kit can be purchased anywhere from $60-$1200 depending on the scale and complexity of your plans. A fully automated, large scale, professional hydroponics system can go into the tens of thousands of dollars. Luckily GrōHaus has plenty of affordable options for people of all budgets! Check out our Hydroponic Starter Kits to browse our selection!
Most plants grow fantastically in a hydroponic setup, save for crops like potatoes, onions, or other tuberous veggies. Plants that grow tall may not be ideal either due to the lack of a root structure implanted in soil, however by utilizing trellis or other plant support methods you can grow taller plants easily in your hydroponics system.


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