Hello elmim1,

From the sound of your desciption I believe you have algea growing or possibly (remote) a moss, and not mold. Most molds are white, some brownish.

Not sure how harmfull it is, but since this is outdoors and I assume water/fed to waste it won't at least clog up plumbing, pumps or a rez.

Are these plants in the ground or in containers?
One possible solution would be to mix a mild solution of FOOD GRADE hydrogenperoxide and water, then spray that on your grow medium.

Maybe someone else that's seen green where it didn't belong can chime in.
Good luck.
oldmac Reviewed by oldmac on . mold issues with troubleshooting form filled out outdoor coconut hulls derived starting plugs CSL-Soil type/brand - sunleaves super starter plugs SCL-Anything you have added to the soil - advanced nutrients micro grow bloom SCLR-Soil or slab runoff pH - i dont know E-Water source - aerated bottled water E-Source water pH - 6.0 E-Age of plant - 2 weeks E-Type of fertilizer - advanced nutrients micro grow bloom E-Lighting source and distance from plant - sun Rating: 5