Note: If you do use solo cups, make sure to cut holes into the bottom so that water can drain out after you’ve watered your plants. Always test to make sure water runs through cup freely. If you have a hard time filling up an empty solo cup with water because it’s running out the bottom, you have added the right amount of drainage.
This will make about 10 gallons of potting mix, just enough potting mix for…
Often when growing cannabis in coco coir, it is helpful to supplement with extra Calcium and Magnesium as calcium deficiencies & magnesium deficiencies are relatively common in coco coir. There are many supplements that provide a boost of these nutrients, and pretty much all of them will work fine. A commonly seen one called “Cal-Mag” by Botanicare works well (and is pretty inexpensive), and so does “CaliMagic” from General Hydroponics. Coco coir is an excellent growing medium as long as you maintain the pH between 5.5 – 6.5 and make sure the plants have enough calcium and magnesium.
First let the majority of the extra water drain out into the bucket, then place the liner in the tub or on the ground so it can continue to let water drain out slowly.
Whenever using liquid nutrients, you will need a way to test pH so your plant roots are able to easily absorb all the nutrients they need. I use a simple General Hydroponics pH test kit. Learn more about managing pH here: https://www.growweedeasy.com/ph
I use a 10-gallon fabric container from Mad Farmer (basically a Smart Pot by a different company) because it’s sturdy, has handles and will stand up on its own after adding coco coir. You could use a 10-gallon Smart Pot, two pillow cases stacked inside each other, or any other fabric container that lets water through and is tough enough to hold 5 gallons of soil.
I have used Shultz, Espoma, Black Gold, and even Miracle-Gro brand perlite. Any 8-quart bag of perlite will work. Perlite can often be found in garden stores or the garden section of places like Home Depot and Lowes. I normally advise against all things Miracle-Gro, but their 8-quart bag of perlite is okay for this tutorial if you can’t find anything else. But remember, never use Miracle-Gro soil or their standard nutrient formula!
In addition, compared to soil, water drains from coco easier and faster. This allows you to feed your plants more often, and in turn grow larger plants.
Once your coco coir is ready, you can fill your growing pots. Next, you’ll want to water your plants. Properly watering your plants will determine how successful your coco harvest will be.
Optimal Water Retention and Drainage
One of the biggest challenges with soil is that it may or may not have all the nutrition your plants need. Even more challenging is trying to supplement nutrients and balance pH levels without spiking their feedings.
- Find the right coco coir medium for your grow setup.
- Growers who use top-feed setups or ebb and flow hydroponics systems with buckets should use loose coco mixed with perlite.
- Growers who use deep water culture (DWC) hydroponics, or who prefer working with clay pebbles, should use coco chips.
What Nutrients Will I Need?
Coco coir is exceptionally great for root development. This is due to coco’s ability to take in nutrients in high amounts, retain those nutrients, and still allow for water wicking.