Fighting mold and dirt on your dioramas

[TheNordus]

Mould, mold, mildew, the stuff that likes to grow on organic things. Maybe because I'm a non-native english speaker I couldn't find information on this. I just remember vague warnings that if you use things scavenged from nature (e.g. dirt, twigs, plants) on your dioramas, mold might start to grow on them. Has that ever happened to you? How do you prevent it?
In addition, how do you keep your collection clean and presentable? I know dust likes to gather on model kits and if you let it stay it turns into dirt that is really hard to get off.

[Stokesy44]

Mould, mold, mildew, the stuff that likes to grow on organic things. Maybe because I'm a non-native english speaker I couldn't find information on this. I just remember vague warnings that if you use things scavenged from nature (e.g. dirt, twigs, plants) on your dioramas, mold might start to grow on them. Has that ever happened to you? How do you prevent it?
In addition, how do you keep your collection clean and presentable? I know dust likes to gather on model kits and if you let it stay it turns into dirt that is really hard to get off.

I haven't used real dirt and flora in my dios but as for dust building up on completed builds, a good spray with the airbrush works a treat - without any paint obviously

[Twokidsnosleep]

Interesting thought, haven't had my dios long enough to see
I give the lichens in the Dagobah swamp a touch of water every once in a while to keep them moist
Anything that grows in the swamp will just add to the realism I suppose

[Vindicare]

if you use real dirt you need to prepare it.

like here:

[youtube]ToF1Do_HPag[/youtube]

he says to place the dirt in the oven minute 2:10