Coconut coir, or coco coir, is one of the most popular growing mediums for everything from ferns to cucumbers.
Coco coir delivers nutrients directly to your plants during every feeding cycle, and it also retains nutrients so you don’t have to water your plants as frequently as you would with a hydroponics system.
While coco coir is beneficial for plant growth, it is most helpful when it’s watered and tended to properly. Taking care of plants grown using coco coir can be tricky, but it doesn’t have to be. That’s where this guide comes in. Here you’ll learn everything you need to know about coco coir and how to water your plants when using coco as a grow medium.
Table of Contents
- What Is Coco Coir?
The Benefits of Coco Coir
- How Do I Use Coco Coir?
- What Nutrients Will I Need?
- How Often Should I Water My Plants?
- Growing with Coco Coir
By the end of this guide, you'll be able to grow your very own plants using coco coir!
Coco coir is a grow medium that consists of brown and white fibers — these fibers comprise the material between the shell of a coconut and its outer husk. The brown fibers come from older coconuts and are fairly strong. The white fibers are taken from younger, less ripe coconuts and are more flexible.
The brown and white fibers in coco coir are removed from coconuts, processed, dried, and prepped for storage. These fibers are then packaged in a variety of ways, including:
- Loose material in bags, like Root Royale and BioBizz Coco-Mix (usually mixed with perlite). Coco coir in this form can be packed into pots, similar to soil or ebb and flow hydroponic systems.
- Chips (similar to wood chips) like Nutrifield Coco Chips Blend 50L. This can be used in hydroponic grow systems and top-feed grow rooms alike, with the added bonus of more airflow.
- Densely compacted bricks which can be broken down and used like loosely packaged coco.
There are many advantages to using coco coir as a growing medium over soil or even coco pebbles.
Coco coir is one of the simplest growing mediums you can use for growing. Soil can be tricky to amend when nutrients and pH are off, and full-on hydroponics can be a little daunting for beginner growers. With coco coir, though, you can feed your plants all the nutrition they need without guessing what they’re already getting like you would have to with soil.
At the same time, coco coir has enough water retention so that you don’t need to be constantly monitoring your garden like you would with hydroponic systems that use rockwool or hydroponic pebbles.
If you decide to take the leap to hydroponic growing from soil, using coco coir is an easy way to make the transition from one to the other because you’ll already know how to feed your plants nutrient-rich water.
Coco coir has no nutritional value. That may seem like a strange thing to highlight, but it actually removes a lot of guesswork when feeding your plants.
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.
As such, coco coir is basically a clean slate. You can give your plants the exact nutrients they need to ensure they’re getting the proper — and correct — nutrition.
Coco coir is one of the best growing mediums when it comes to retaining and draining water. It has the ability to hold as much as 10 times its weight in water. Unlike hydroponic pebbles that are meant to wick water away, coco has the ability to retain water so you’re not having to constantly run a system to ensure your plants are being fed.
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.
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.
Without plenty of oxygen, root systems will stay small, thus keeping your plants small. At the same time, too much oxygen means you’re drying off and harming your roots if you’re not on top of your watering schedule. Coco coir offers a unique blend of nutrient retention, quick drying, and airflow that soil and hydroponic pebbles have a hard time doing efficiently.
Most insects and other pests that can damage your plants don’t like coco coir. Pests tend to land in soil because of the nutritional value they can obtain from it, but coco serves them no purpose, so they tend to stay away. In fact, other than fungus gnats, pests aren’t typically attracted to coco coir.
It’s worth noting that pests will always be attracted to your plants, so it’s always important to practice proper pest prevention and elimination. Still, coco deters more pests from landing on your plants because they know they can’t stay for long if they do.
Coco coir is made with recyclable and reusable materials, which means you can extend its life beyond just a few growing cycles. Unlike pebbles that are usually thrown out after each grow, or soil that needs to be rejuvenated with nutrition, coco coir is easier to maintain and keep reusable after multiple grows.
If you plan on reusing coco coir, you’ll have to let it dry first and then remove any plant stems and other debris after a growing cycle. Other than that, you’ll be good to go and your coco will be ready to reuse.
We've outlined the steps for preparing coco coir for your next growing cycle. It's actually pretty simple.
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.
Mix your coco coir and perlite (not necessary with chips). The amount of perlite you add to coco will determine the amount and frequency you give plants nutrient-rich water. Remember: The more perlite you add, the less water coco will retain.
- Using 25 percent perlite will give you a 3:1 mixture of coco to perlite, which is what we recommend for hydroponic systems, whether you’re using an ebb and flow system like the GreenTree Hydroponic system or a drip system like the Versagrow.
- A 30 to 50 percent perlite mixture will retain less nutrients, which will require you to water your plants more often. Still, you’ll find big grow ops using perlite mixes of up to a 50/50 pushing out big harvests.
- More than 55 percent perlite in coco will do virtually the same thing as soil, except you’ll need to provide all of the nutrition.
Prepare your coco coir for transplanting.
- Fill your buckets with coco and rinse it thoroughly with clean water. This will wash out any imperfections that may be present in the coco.
- If you’re using coco bricks, start by soaking the bricks to break them down. Let the coco bricks dry, and then give them another thorough rinsing before setting them up.
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.
The last thing you’ll want to know before you start feeding your plants is what you should be feeding them.
Unlike other growing mediums, coco coir is not a nutrient-rich solution. As such, you’ll need to use nutrient-enriched water or provide additional nutrients. This technique, also known as fertigation, consists of mixing nutrient-rich solutions and fertilizers with water.
When you are able to properly fertigate your coco, you will achieve the best results with your plants. Here are the nutrients your plants will need if you use coco coir:
The best way to ensure you are providing your plants with the proper nutrients is to buy a fertilizer or nutrient set specifically made for growing with coco coir in potted plants or with a hydroponics system. General Hydroponics and Dyna Gro, for example, are great for coco coir grows because of the complete nutrition they’re able to provide.
- Make sure to maintain an optimal pH when feeding your plants. Because it's pH neutral, you can treat coco like hydroponics, whether you're using it in a hydroponic system or drain-to-waste in buckets.
- Most hydroponic plants need a pH of anywhere between 5.3 to 6.5. Plants vary on needs, however, so double check what's needed for your specific plant.
- While you'll need to stick close to your feeding schedule, check the strength of your nutrients. Some may need to be diluted a bit while your plants are young, or heavily diluted depending on the concentration and content.
While your watering schedule will depend on the type of plants you’re growing, it is definitely vital that your coco coir is always wet. You should never allow your coco to dry out, as this will prevent your plants from getting the necessary nutrients.
Here are a few tips to keep in mind when watering your plants in a coco coir medium:
Water top-fed plants until you see water coming from the bottom. Just like soil, it’s time to stop feeding once 10 to 20 percent of the water used for your plants runs out of the bottom when using coco coir.
- At the beginning of your grow, you'll only need to water your plants once every one to two days. As your plants grow, feeding intervals will increase, so don't be surprised if you have to feed your plants more than once a day when they flower.
For the average hydroponics system, coco coir needs to be flooded every three to five hours. You will have to gauge your system to make sure you’re still maintaining 95 to 100 percent saturation and adjust your flood cycle accordingly.
- Monitor your coco saturation. Ideally, your coco coir should be 95 to 100 percent saturated at all times. When your coco coir has lost 5 percent of the total amount of water it can hold, you’ll need to water it again.
- Note: If you pinch a little coco off the top, it should give you some moisture, but not much. Lots of water running out means plants are overwatered. No water running out means it’s probably time to feed. Alternatively, If your coco coir medium is in a pot, you will notice that the pot feels light when the coco coir is too dry.
- Increase watering frequency over time. As your plants grow, it’s important to make sure you are watering them more frequently as they will require more water during the later stages of their development. You may find yourself flooding at least three to four times at day toward the middle of your growth cycle, and even more often toward harvest time.
Like any growing medium, coco coir has its intricacies and requires that you know what you’re working with. By directly feeding your plants and retaining both water and nutrients, it’s a unique and effective growing medium.
It’s also simpler to use than soil and pebbles, making it a more approachable medium whether you’re a beginner or a long-time grower.
Now that you know what coco coir is and how it’s properly used, you’ll be ready to use it for your next grow. And thanks to its reusable properties, you’ll be able to keep using it for multiple subsequent grows.