Quote: >There is some black thing that develops on the >surface of the compost and roots of my orchids after 1 or 2 years of >culture. Could anyone help me identify what the problem is and >what's the cure?
It is probably an alga, which seems to have originated from a nursery in the Netherlands and then spread around. Does it develop vaguely moss-like growths from old leaves and roots, and peel off leaves when mature? There is nothing that deals with it except snails, which have other down-sides. The answer is to stop fertilization for a year, whereupon its growth on new leaves ceases and it can easily be washed off older leaves. Re-pot and the black cap issue is also removed. Basically, I think, it signals that you have been over-fertilizing, and getting fertilizer onto the leaves. ______________________________ Oliver Sparrow +44 (0)20 7736 9716 www.chforum.org _______________________________________________ the OrchidGuide Digest (OGD) [email protected] http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
