Quick verdict: Perlite = drainage & airflow. Vermiculite = moisture & nutrient hold. For seedlings or thirsty plants, reach for vermiculite; for cacti or chunky aroid mixes, lean on perlite—or grab our ready-blended 50/50 and skip the guess-work.
What Is Perlite?
Perlite starts life as volcanic glass that “pops” like popcorn when super-heated, trapping thousands of tiny air pockets. The result? A sterile, pH-neutral (≈ 6.6–7.5) white granule that’s feather-light yet physically strong. In mixes it:
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Loosens heavy soils so roots can breathe.
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Speeds drainage—ideal for succulents, citrus, ginger & any plant that hates wet feet.
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Keeps potting blends lighter for balcony pots and hanging baskets.
Grab it: Our Exfoliators Perlite Coarse 3-6 mm ships in handy 10 L to 100 L bags and is squeaky-clean, low-dust, and Aussie-mined.
What Is Vermiculite?
Vermiculite is a natural silicate mineral that expands into golden, worm-like flakes when heated. Each flake acts like a sponge—soaking up 3–4 × its volume in water and locking onto nutrients such as potassium, calcium and magnesium. In mixes it:
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Keeps seed trays evenly damp to prevent fatal dry-outs.
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Buffers pH around neutral and gently raises acidic soils.
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Slows down nutrient leaching—handy in sandy, free-draining Aussie beds.
Grab it: Our coarse Ausperl Vermiculite 3-6 mm is sterile, lightweight and perfect for propagation, hydro or wicking beds.
Side-by-Side Cheat Sheet
|
Feature |
Perlite |
Vermiculite |
|
Texture |
White, airy granules |
Gold-brown flakes |
|
Water-holding |
Low |
Very High |
|
Aeration/Drainage |
Excellent |
Moderate |
|
Weight When Wet |
Light |
Noticeably heavier |
|
Ideal Uses |
Cacti, aroids, drainage fixes, clay-break-up |
Seed starting, moisture-loving herbs (mint, parsley), wicking beds |
|
pH Impact |
Neutral (6.6 – 7.5) |
Neutral-to-slightly alkaline (~7) |
When to Use Perlite
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Potting mixes for indoor jungle plants that prefer to dry between drinks.
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Bulking up heavy loam or clay soil—mix 10–20 % by volume.
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Hydroponic/aquaponic systems needing high dissolved oxygen.
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Rooting cuttings where rapid callusing beats excess moisture.
Dr Greenthumbs tip: Dust can irritate lungs—pre-moisten perlite before blending.
When to Use Vermiculite
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Covering germinating seeds to keep them consistently moist.
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Mixing into wicking barrels or SIP planters for capillary action.
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Buffering sandy coastal soils that dry out in summer nor’easters.
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Short-term rooting of cuttings that hate drying out (coleus, basil).
Best Mix Ratios & Pro Tips
Seed starting: 70 % vermiculite / 30 % coco coir for spongy moisture.
General potting: 30 % perlite / 20 % vermiculite / 50 % premium compost.
Aroids & succulents: Up to 40 % perlite for chunky airflow.
Too busy to measure? Our Perlite & Vermiculite Mix 50/50 comes pre-blended, sterile and ready to pour—ideal for propagation trays or topping up existing blends.
FAQs for Aussie Gardeners
Q. Can I reuse perlite or vermiculite?
A. Yes. Rinse well to remove salts and let dry in the sun to sterilise.
Q. Is asbestos a concern in modern vermiculite?
A. Not with horticultural-grade products like ours—each batch is heat-expanded and tested to ensure zero asbestos fibres.
Q. Will perlite blow away in outdoor beds?
A. It can on windy days. Work it 5 cm below the soil surface or wet it down after spreading.
Q. How long do they last in soil?
A. Both are inert minerals that don’t break down, so one application keeps working for years.
Ready to Super-Charge Your Soil?
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🌱 Shop Perlite: Exfoliators Coarse Perlite
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💧 Shop Vermiculite: Ausperl Coarse Vermiculite
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🪴 Grab the Mix: Perlite & Vermiculite 50/50 Blend
Order before 2 pm AEST for next-day dispatch Australia-wide.
Happy growing!
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