1. The nightmare every indoor gardener knows too well
If you’ve ever battled fungus gnats, you know how draining it feels.
They start small, a few harmless flies buzzing near your Monstera, but before you know it, they’re everywhere. Around your windows, hovering above your soil, hiding in your compost.
Like many home gardeners in Vancouver, I thought I was doing everything right:
✅ Using organic compost
✅ Keeping the soil moist for healthy roots
✅ Letting air circulate near the pots
And yet, week after week, the infestation only grew worse.
The problem wasn’t my plants it was the medium I was using.
2. Where fungus gnats really come from (and why compost makes it worse)
Here’s the truth most people don’t realize:
Fungus gnats breed in organic matter, not just in your houseplants. Their larvae feed on decaying plant material, fungi, and the moist upper layer of soil.
That means compost, peat-based soil, or even overwatered potting mix can become a perfect nursery for them.
Even if your home is spotless, you can still get an infestation from outside – especially if you live in shared garden areas, apartments, or townhouses around Vancouver where gnats easily travel between spaces.
Every time I watered my indoor plants, I was unknowingly giving those larvae exactly what they needed: moisture and food.
So I decided to go radical — remove the very thing they thrived in.
3. The Switch: From Compost to 100% Perlite Propagation
I’d read about perlite propagation before but never thought it could fully replace soil.
Desperate to stop the gnats, I decided to try it.
And the results? Honestly — life-changing.
Within two weeks:
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The gnat population dropped to zero.
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My Monstera roots exploded with new white roots.
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Even my snake plant — which had been sitting still for months — started pushing new shoots.
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My umbrella tree began branching again after staying dormant for nearly a year.
I realized something powerful:
👉 You don’t always need soil to grow strong plants indoors.
👉 Sometimes, plants thrive even better in a clean, airy medium like perlite.
4. Why Perlite Propagation Works So Well
Let’s break it down for science-minded gardeners:
Perlite is a volcanic glass that expands when heated. It’s sterile, airy, and completely free of organic matter. That means:
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No food for fungus gnat larvae
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Excellent aeration for roots
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Fast drainage (no soggy soil)
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Lightweight and reusable
When you switch from compost to perlite propagation, you eliminate the two key things fungus gnats need — moisture and decay.
That’s why my jars and vases stayed pest-free for months, even during Vancouver’s humid fall season.
5. How to Start Perlite Propagation (Step-by-Step)
If you want to try this at home, here’s how I do it — simple and effective:
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Choose a transparent jar or vase.
– Glass vases work great for monitoring roots. -
Rinse your perlite.
– Dusty perlite can clog pores and irritate roots. Wash it in a fine mesh strainer until water runs clear. -
Add perlite to your container.
– Fill about ¾ of the way. -
Moisten it lightly.
– Add just enough water to dampen the perlite — not soak it. -
Insert your plant cutting or root ball.
– Make sure the roots touch the damp perlite but aren’t drowning in water. -
Place near bright, indirect light.
– Perfect for tropicals like Monstera, Pothos, Umbrella Tree, Snake Plant, and even Cactus pups. -
Change or top-up water every 1–2 weeks.
– Keeps the environment fresh and oxygenated.
6. Common Questions Gardeners Ask
“Will my plants get enough nutrients without soil?”
→ Once your plants have strong roots, you can transfer them into a soil mix or supplement with a mild liquid fertilizer (like organic seaweed extract from DH Garden Centre).
“Can I use this method for succulents?”
→ Surprisingly yes! Just keep perlite slightly damp, not wet. Many succulent cuttings root beautifully this way.
“How long can plants stay in perlite?”
→ As long as you maintain moisture balance, indefinitely. I’ve had Monsteras thriving in perlite for over 6 months!
7. What I Learned After 4 Months of Perlite Living
Three months in, I noticed something amazing:
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My root growth doubled compared to traditional soil.
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No more pests.
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No sour smell from compost.
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And — my indoor space felt lighter, fresher, cleaner.
For the first time in years, I wasn’t swatting tiny gnats during dinner or worrying about larvae under the surface.
This experience reminded me why I fell in love with plants in the first place — the peace and growth they bring, not the frustration.
8. The Science Behind Fungus Gnat Prevention
Here’s a quick breakdown of why this works long-term:
| Problem | Cause | Solution |
|---|---|---|
| Fungus gnat infestation | Moist organic soil | Use sterile, non-organic media like perlite |
| Larvae in soil | Overwatering | Keep roots airy and let medium dry between waterings |
| Reinfestation | Nearby compost or mulch | Keep houseplants separate from compost bins |
| Weak roots after switch | Too little humidity | Mist occasionally or use humidity trays |
Perlite creates an environment that supports healthy oxygen flow and discourages pests. Combine that with bottom watering and moderate humidity, and you’ve got the perfect indoor growing system — especially for Vancouver’s rainy season.
9. What You’ll Need (and Where to Get It)
At DH Garden Centre, we carry everything you need to start your perlite journey:
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Premium horticultural perlite — sterile, lightweight, ready to use.
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Organic rooting hormone to speed propagation.
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Clear glass jars and propagation vessels.
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Seaweed and fish-based fertilizers for nutrient support once roots develop.
You can find them all at 3742 West 10th Avenue, Vancouver, BC V6R 2G4 — or order online at dhgardencentre.com.
10. A Message to Every Gardener Tired of Fighting Fungus Gnats
If you’ve been battling fungus gnats, I know how hopeless it can feel.
But the truth is, sometimes the solution isn’t adding more traps or sprays — it’s rethinking the way we grow.
Switching from compost to perlite propagation not only ended my pest problem but also gave my plants new life.
So if you’re struggling with gnats right now, don’t give up. Try this method.
You might just fall in love with growing all over again.
🌿 Ready to Start?
Come by DH Garden Centre in Kitsilano or visit dhgardencentre.com to get everything you need for your perlite propagation setup.
Let’s grow cleaner, healthier, pest-free plants together — because a gnat-free home is a happy home.
FAQs
1. Do fungus gnats live in perlite?
No. Perlite contains no organic material for larvae to feed on, so fungus gnats can’t survive there.
2. Can I mix perlite with soil instead of going full perlite?
Yes! A 50:50 mix of perlite and potting soil reduces moisture retention and helps prevent gnat breeding.
3. How do I dispose of infested soil safely?
Seal it in a bag and leave it outside for at least a week before composting. Never mix it with clean soil.
4. Does perlite propagation work in winter?
Absolutely. In Vancouver’s low-light months, just move your cuttings closer to a bright window or use a grow light.
