Springtails: where to find them and how to use them

Springtails (Collembola) are tiny arthropods, usually 1-3mm long, that live in moist soil and eat mold, decaying matter, and fungi. In a closed terrarium they are not optional — they’re the cleanup crew that keeps your build alive.

What they actually do

• Eat mold spores before they spread
• Break down dead plant matter into nutrients
• Aerate the substrate
• Compete with harmful mites and fungi

A terrarium with an established springtail colony is dramatically more stable than one without. They reproduce fast, are self-regulating, and won’t bother your plants.

Where to buy starter cultures

• Josh’s Frogs — best quality, ships well, $15-20
• The Bio Dude — bulk options, terrarium-focused
• Etsy — search “springtail culture”, many small sellers
• Local terrarium builders (Facebook groups) — often free or trade

The shipped vs local choice

Shipped: arrives in 2-7 days, may have die-off in transit (still viable if you see movement in the culture). Local: free or cheap, no shipping stress, you can see them before you buy.

How many do you need?

For a small jar (quart-sized): 1 tablespoon of culture. For a medium build (2-5 gallons): 2-3 tablespoons. For a large build (10+ gallons): 1/4 cup.

They multiply fast. Start with what feels like too little, they’ll fill in within a month.

How to introduce them

1. Open your terrarium
2. Dump the culture (substrate + springtails) onto the soil surface
3. The springtails will burrow down within hours
4. Close the lid

That’s it. They don’t need to be “planted” — they’ll find their own spots.

Keeping the culture alive (separately)

Most sellers send extra culture so you can grow your own:

• Small plastic container with ventilation holes
• 1 inch of charcoal (horticultural, not aquarium) at the bottom
• 1 inch of dechlorinated water above the charcoal
• Sprinkle yeast or fish food flakes weekly
• They will colonize everything in 2-3 weeks

This way you never run out.

Common concerns

Will they escape the terrarium? No. In a closed jar, they’re trapped. In an open terrarium, they’re so small you won’t notice them, and they die quickly in dry air.

Are they harmful to plants? No. They eat dead organic matter and fungi, not living plants.

Can I have too many? In a healthy closed terrarium, they self-regulate based on food supply. In an open one, they’ll die back if the substrate dries.

The cheat sheet

Need springtails for	Buy from	Cost
Single small jar	Etsy seller, local group	$10-15
Multiple builds	Josh’s Frogs bulk	$20-30
Just experimenting	Local breeder (often free)	$0

Pairing with isopods

Springtails + isopods = full cleanup crew. Isopods eat larger debris, springtails handle the small stuff. Together they keep any bioactive terrarium balanced.

For more on isopods, see our isopod sourcing guide.