Q & A: Can I use spanish moss instead of sphagnum moss in my terrarium?

Image courtesy of http://www.orchidsandtropicals.com/

This week I received an excellent question in my post "How to Make a Terrarium: Adding Soil Layers."

Question: Can dried spanish moss be used in lieu of the spaghnum moss as a filter?

Answer: Sphagnum or peat moss is a commonly used element in gardening and container gardening but I have never seen spanish mossed used in the same capacities (i.e. to line a hanging wire flower basket).  I did some research online and found an ehow article that may help us.  The author points out that while sphagnum moss is a great water absorber, spanish moss is actually an air plant in the tillandsia family and will not act the same way when used in gardening.

I'll paraphrase some of the key points here:

"Spanish moss is home to small insects and other organism. Spanish moss requires treatment or sterilization before use.... Because sphagnum moss grows in highly acidic waters, peat moss is usually germ free.  Because of its water-retaining ability and lack of most pathogens, it is ideal for seed-starting mixes or use as a soil amendment.  Spanish moss, does not incorporate easily into soil, but does act as an effective mulch, especially for indoor potted plants."

Read more: Spanish Moss Vs. Peat Moss

The idea of the Spanish moss potentially containing contaminants makes me hesitant to suggest using it as a terrarium soil layer.  You'll want to minimize the inclusion of any mold or germs in your terrarium.