Make your own black gold.  Turn unwanted kitchen scraps into a rich fertilizer for your plants.  The staff at the Lyman Estate Greenhouses, 185 Lyman Street in Waltham will teach you how to set up a home composting bin. Topics in this two day class to be held Friday, November 19 and Saturday, November 20 from 10 – 12 include choosing the right bin, feeding and maintaining your worms, and havesting your compost.  Registration is required. Please call 781-891-1985 for additional information, or log on to www.historicnewengland.org.  The fee is $20 for Garden and Landscape members, $25 for Historic New England members, and $35 for nonmembers.