Vermiculite
Holds three to four times its own volume in water.
Brunnings Propagation Vermiculite is a hydrated magnesium iron aluminium silicate, heated until it exfoliates into lightweight accordion-shaped granules, in 25 litre bags. It holds three to four times its volume in water, and it holds calcium, potassium and magnesium in the root zone where a plant can reach them.
Or call the yard on (08) 9434 2290
Real stock, not a swatch. Blended products vary a little batch to batch, so treat these as a guide rather than an exact colour match.
Vermiculite details
Vermiculite at a glance
- Product type
- Exfoliated mineral
- Brand
- Brunnings Propagation Vermiculite
- Pack
- 25 litres
- Water holding
- 3 to 4 times its own volume
- pH
- About neutral
- Sterile
- Yes
What Vermiculite suits
What can you use Vermiculite for?
Seed raising
A light topping over seed keeps the moisture even, which is the single biggest factor in whether seed germinates evenly or in patches.
Potting mixes that dry out
Blended through, it holds water where a pot on a hot windowsill would otherwise be bone dry by afternoon.
Sandy soil
Brunnings list moisture retention in sandy soils, which in Perth is not a niche use case.
Hydroponic media
Sterile, inert and it holds both water and nutrient, which is a useful combination in a soilless system.
How much Vermiculite do you need?
A proportion, or a dusting
Vermiculite is blended into a mix or scattered over seed, so there is no coverage rate. What matters is the proportion, and it depends entirely on which of the two jobs you are doing.
Both figures below are the standard propagation practice Brunnings sell it for.
| Job | How much | What a 25L bag does |
|---|---|---|
| Topping seed trays | A light dusting over the seed | A very large number of trays. This is the cheap use. |
| Blending into a potting mix | 10 to 30% by volume | 80 to 250 litres of finished mix, depending on the rate. |
| Improving a sandy bed | Worked into the top of the soil | Ask us — for a whole bed, clay is far better value than vermiculite. |
It has no nutrients of its own. It holds what you provide, so seedlings still want feeding once the seed's own reserves run out — which in a high-vermiculite mix is sooner than most people expect.
Why Vermiculite
Why choose Vermiculite?
It holds three to four times its volume in water
That is the headline number and it is what you are buying. A mix with vermiculite through it stays damp far longer than one without.
It holds nutrient, not just water
Calcium, potassium and magnesium held in the root zone. Perlite cannot do this — it is inert in every sense.
Sterile, and about neutral
No pathogens, no weed seed, and a pH that will not fight whatever you are growing.
A light topping keeps seed evenly moist
The classic use, and the one most worth knowing: it is why seed raised under vermiculite comes up evenly.
Getting Vermiculite home
How to get Vermiculite
Collect from the yard
Open seven days at 222 Barrington St, Bibra Lake. The loader puts it straight into your trailer or ute, and someone will tell you whether what you have brought will carry the load.
Borrow one of our trailers free for two hours to get your load home. No charge, no bond.
Have it delivered
Across Perth's southern suburbs, seven days. For a quote we need the address, how much you need, and anything awkward about access — tight driveways, low branches and side access all change which truck we send. Confirm the current cost when you order.
Formats
- Loose, by the cubic metre
- Bulka bag, roughly a cubic metre each
- Trailer load, including our free two hour trailer
Using Vermiculite
How to use Vermiculite
Use fine for seed, medium for potting
Fine grade as a light topping over seed, medium grade blended into a potting mix. They behave differently enough to matter.
Top seed lightly
A thin covering, not a burial. The point is even moisture at the seed, not depth.
Blend it through a mix
Mixed in rather than layered. A band of vermiculite in a pot is a wet layer, not an improvement.
Wear a mask if it is dry
Dusty when dry, like most mineral products. Damp it down or wear a mask.
When to choose something else
When it is the wrong product
- It has no nutrients of its own. Seedlings will need feeding once the seed's own reserves run out, and in a high-vermiculite mix that happens sooner than you expect.
- It holds water, which is a problem as well as a feature. In a mix that is already too wet, adding vermiculite makes it worse — that is what perlite is for.
- It is dusty when dry. Damp it down or wear a mask while you are working with it.
- It is a component rather than a growing medium. On its own it will germinate seed and then run out of everything.
Customer reviews
What people say
Vermiculite questions
Vermiculite FAQs
Goes with Vermiculite
Other products you may need
The other half of the pair
Vermiculite holds water. This adds air.
What you are blending it into
The mixes vermiculite improves.
Holding water in a whole bed
Vermiculite is for pots and trays. These are for ground.
Guides for vermiculite
Planning your project
Vermiculite quote
Need Vermiculite for your project?
Send us the quantity you need, your suburb, and whether you would like to collect it or have it delivered. If you are not sure how much, put your measurements into the calculator above and we will check it for you.
Or ring the yard on (08) 9434 2290
222 Barrington St, Bibra Lake WA 6163 · Open 7 days
Use the calculator above and the amount lands in the message for you.