First I'd like to thank all those who offered ideas about the possible reason for the decline of the Arums. It seems the issues fell into a number of categories. Light-both intensity and duration Soil moisture Temperatures Fertilizer I can elaborate on the position that the plants in question occupy in the greenhouse. They are against a west facing wall which is opaque to sunlight. In the winter the sun probably hits them around 1 PM They get artificial light starting around 11 AM from two T-5 LED fixtures with four tubes (6500K) in each lights go off at 7 PM. I have looked at the curled leaves with a jewelers loop and haven't been able to see any mites, aphids or other insects. I've un-potted them last year and replaced the soil with standard potting mix. The tubers and pots were sterilized with a commercial solution we use at work to clean tables between patient use. I'm a physical therapist. It is a solution also used in restaurant at the end of the night. The surfaces are spayed and allowed to air dry. Something similar to what is used to clean an OR prior to conducting a surgical procedure. The high temperatures in the greenhouse on a sunny day can reach 60 F. I think it would be much too cold outside at this time of year for them. We can get 12-15 F at times. When I un-potted them last year the tubers showed no signs of rot. I have fed them only once this year about three weeks ago with the DTE all purpose mix. Based on comments from Gianluca and Luminita I'm going to put them under the greenhouse bench when they will get considerable less light and possible a bit cooler. Prior to having the greenhouse built they lived in the basement under standard fluorescent lights and flowered. I'll let everyone know how they make out. Thanks again for the fruitful discussion. Arnold _______________________________________________ pbs mailing list pbs@lists.pacificbulbsociety.net http://lists.pacificbulbsociety.net/cgi-bin/…