Driftwood prep: the 4-step method that actually works

Driftwood makes or breaks a terrarium build. A great piece gives you structure and drama. A bad piece — one that floats, molds, or leaks tannins — ruins the build.

Here’s how to pick, clean, and prep driftwood so it works for years.

What to buy (and what to skip)

Best for terrariums

• Mopani wood — dense, doesn’t float, beautiful dark color
• Manzanita — gnarled, dramatic, terrarium-standard
• Spider wood — branching, perfect for epiphyte mounting
• Grapevine — twisted, lightweight, fun shape (but floats, needs weighting)

Skip

• Pine or cedar — contain resins toxic to plants
• Fresh wood (not driftwood) — rots fast, attracts mold
• Treated or painted wood — chemicals leach
• Anything labeled “decorative” — often treated

Where to buy

• Specialty aquascaping suppliers — best quality, terrarium-grade
• Etsy — search “terrarium wood”, many small crafters
• Local fish stores — often sell aquascaping wood
• Your local woods (if experienced) — see ethics note below

Ethics note

Never collect driftwood from protected areas (state parks, nature preserves). If you do collect from your own property or public land where permitted, choose pieces that are already detached and dry.

The 4-step prep method

Step 1: Initial rinse (5 minutes)

• Rinse off loose dirt and debris
• Use a stiff brush for stubborn dirt
• Don’t worry about being thorough yet

Step 2: Bleach bath (24 hours)

• Mix 1 part bleach to 9 parts water in a bucket
• Submerge driftwood completely
• Weigh it down (it’ll float)
• Soak for 24 hours to kill mold, bacteria, insects

Skip this step if: You’re using commercially-sold terrarium wood (already treated).

Step 3: Fresh water soak (3-7 days)

• Drain bleach bath
• Refill with fresh water
• Soak for 3-7 days, changing water daily
• This leaches out tannins (the stuff that turns water brown)

Tannins are not harmful — they actually slightly acidify water, which most terrarium plants love. But heavy tannins = dark tea-colored water. Some people like the look; most don’t.

For minimal tannin leach: soak longer, change water more often.

Step 4: Final rinse and dry (24 hours)

• Final rinse with clean water
• Pat dry with towel
• Let air dry completely (24 hours)
• Now it’s ready to use

Solving the floating problem

Even after all this prep, some woods (grapevine, lighter pieces) will still float. Solutions:

• Glue to base — use aquarium-safe silicone to attach to a rock
• Weight with substrate — bury part of it deeply in substrate
• Choose denser woods — mopani and manzanita rarely float after prep

The “still leaks tannins” issue

Some woods (especially mopani) will keep leaching tannins for months. Solutions:

• Accept it — many builders like the tea-stained water look
• Activated carbon in your filter (if you have one) or substrate mix
• Replace with a less tannin-heavy wood if it bothers you

Mounting plants on driftwood

Great for epiphytes, moss, and small ferns. Steps:

1. Spread a thin layer of sphagnum moss on the wood where you want the plant
2. Place the plant on the moss
3. Wrap with cotton string or fishing line (the line is invisible once wet)
4. Mist heavily for the first 2 weeks
5. Plant will root into the moss and attach itself

Care after install

Once in your terrarium:

• Spray occasionally to prevent drying out (for mounted plants)
• Wipe off any white growth that appears (usually mycelium, harmless)
• Trim attached plants before they overgrow the wood

When to throw out a piece

If your driftwood:

• Stays soggy and never dries between mistings
• Grows fuzzy mold repeatedly
• Starts to smell bad
• Becomes soft or crumbly

Pull it out and replace. Better to lose one piece than lose the whole build.

The cheat sheet

Wood type	Floats?	Tannins	Best for
Mopani	No	High	Submerged or in substrate
Manzanita	No	Low	Mounting, dramatic shapes
Spider wood	Sometimes	Medium	Branching builds, mounting
Grapevine	Yes	Low	Above-substrate, weighted
Malaysian	No	High	Substrate-only

For more on hardscape sourcing and ethics, see our hardscape on a budget guide or post in the Discord.