Coco Coir vs Perlite: Should You Use a Coir Brick or a Coco Perlite Mix?

Coco coir and perlite aren't really rivals. Coco coir is shredded coconut husk that soaks up and holds water; perlite is expanded volcanic glass that holds very little water itself and keeps the mix open and airy. That's why most growers use them together rather than choosing one.

The short answer: use coco coir on its own for seedlings and moisture-loving plants, and add perlite when a plant needs faster drainage. A 70/30 coco-to-perlite mix suits most plants, and you can go up to 50/50 for succulents (see the ratio table below).

In practice, the choice most home growers face is between a compressed coco coir brick, which you rehydrate and blend yourself, and a ready-made coco perlite mix. We compare both below.

What Is Coco Coir and Why Is It So Popular?

Coco coir is a natural growing medium made from the fibrous husks of coconuts. It's the brown, spongy material found between the outer shell and the inner coconut. Once considered agricultural waste, it's now one of the most popular growing mediums in modern horticulture and for good reason.

Here's why gardeners and growers love coco coir:

• Sustainable and eco-friendly : it's a renewable byproduct of coconut processing
• Near-neutral pH : usually around 5.8–6.8, slightly acidic, which suits most plants
• Excellent water retention : holds moisture without becoming waterlogged
• Reusable : with proper flushing, coco coir can be reused across multiple grows
• Naturally resistant to mold, fungi, and pests

Whether you're growing indoors or outdoors, in pots or raised beds, coco coir offers a flexible, plant-friendly base.

What Is a Coco Coir Brick?

A coco coir brick is compressed, dehydrated coco coir pressed into a compact block. It's lightweight, easy to store, and expands dramatically when water is added making it incredibly convenient for home growers.

Nutrifield Coco Coir Bricks are a premium example of this product. Made from high-quality coconut husks, they're triple-washed to remove excess salts and buffered for optimal nutrient uptake.

How to Rehydrate a Coco Coir Brick

Expanding a coco coir brick is simple:

1. Place the brick in a large bucket or tub
2. Slowly pour warm water over the brick, using the amount on the pack (small household bricks usually take 3–5 litres; a 5kg brick needs far more)
3. Wait 10–15 minutes while the brick absorbs the water and expands
4. Break apart any remaining clumps with your hands
5. Allow to drain slightly before use it should feel like a damp sponge

Small bricks typically expand to 8–10 litres of growing medium, while the 5kg Nutrifield brick expands to 55 litres, which makes it excellent value for the shelf space it takes up.

What Is Coco Perlite Mix?

Coco perlite mix combines coco coir with perlite a volcanic glass material that looks like tiny white beads. When added to coco, perlite creates air pockets in the medium, improving drainage and oxygen flow to the root zone.

Orku's Coco Perlite Mix typically comes in a 70% coco / 30% perlite ratio. This blend strikes the sweet spot between moisture retention (from the coco) and fast drainage with strong aeration (from the perlite).

The result? A ready-to-use medium that reduces the risk of overwatering, encourages faster root development, and supports more vigorous plant growth especially for plants sensitive to wet feet.

Coco Coir Brick vs Coco Perlite Mix: Side-by-Side Comparison

Coco coir bricks give you more control and lower cost. Coco perlite mix saves time and delivers superior aeration straight out of the bag.

Not sure how coco coir compares to regular potting mix? We break it all down in our best potting mix for indoor plants in Australia guide.

Which Plants Prefer Which Medium?

Best Plants for Coco Coir Brick

Coco coir bricks work exceptionally well for plants that prefer consistent moisture:

Best Plants for Coco Perlite Mix

The 70/30 blend shines with plants that demand fast drainage and root oxygen:

How to Use Each Medium (Step-by-Step)

Using a Coco Coir Brick

1. Expand the brick follow the rehydration steps above
2. Check moisture level squeeze a handful; a few drops should fall out (not a stream)
3. Fill your pots or trays pack loosely; don't compress
4. Water with a diluted nutrient solution coco is inert, so nutrients must be added
5. Monitor regularly water when the top inch feels slightly dry

Pro tip:

Coco coir is naturally low in calcium and magnesium. Always use a Cal-Mag supplement alongside your regular nutrients.

Using Coco Perlite Mix

1. Open the bag and check moisture Orku's pre-blended mix is usually slightly moist
2. Fill your containers the mix flows easily and doesn't clump
3. Water thoroughly on first use to settle the medium
4. Feed with nutrients every watering like pure coco, this mix has no inherent nutrients
5. Water more frequently than soil the improved drainage means it dries faster

Pro tip:

The 70/30 blend is ideal for drain-to-waste or recirculating hydroponic systems. It handles high-frequency feeding without becoming anaerobic.

Growing indoors? Pair your coco coir setup with the right lighting see our guide on how to choose the right grow light for indoor plants in Australia.

Can You Mix Them? Absolutely.

One of the best things about both products is that they're fully compatible. Many experienced growers start with a Nutrifield Coco Coir Brick as their base, then blend in extra perlite to customise their drainage level.

Mixing gives you full control over your growing environment and it lets you stretch your budget further by buying the brick and adding perlite separately.

Final Recommendation

For beginners just starting out, the Orku Coco Perlite Mix (70/30) is the easiest choice. It's ready to use straight from the bag, reduces the risk of overwatering, and works well for a wide variety of plants indoor or outdoor garden. There's no measuring or mixing required.

If you're looking to save money, scale up, or customise your mix, grab a Nutrifield Coco Coir Brick. Rehydrate, blend to your preferred ratio, and you've got a premium base medium at a fraction of the cost.

Either way, you're investing in a sustainable, high-performance growing medium that will give your plants a strong foundation to thrive.

Want to put your new coco mix to work? See our favourite vertical planter balcony plant combinations that pair perfectly with coco perlite mix.

FAQ

Can I use coco coir instead of perlite?

Not as a straight swap. Coco coir holds water while perlite adds drainage and air, so they do opposite jobs. Most growers mix them, and 70% coco with 30% perlite suits most plants.

How much water do I add to a coco coir brick?

It depends on the brick size, so check the pack. Small household bricks usually need 3–5 litres of warm water, while a 5kg brick needs much more. Wait about 15 minutes, then break apart any clumps.

How much perlite should I add to coco coir?

Start with 30% perlite and go up to 40% for plants that need extra drainage, or 50% for succulents and cacti.

Are coco coir bricks good for plants?

Yes. They have a near-neutral pH, hold moisture well and are ideal for seedlings, cuttings and herbs.

What plants thrive in coco coir?

Seedlings, herbs, leafy greens and ferns do well in pure coco coir because they like steady, even moisture.