| Gypsum | Comments | 
|---|---|
| GYPSUM: As Top Dressing It can be beneficial for cymbidiums where the water supply has too much sodium; it adds calcium. OD76-122 | 0 | 
| GYPSUM: Supply of Calcium It is not highly alkaline, is available as a powder which should be useful in a tight potting mix but will wash out of a loose or open mix; pellets of it can be made by mixing Plaster of Paris with water, spread out as a thin paste to dry and then broken into flakes for adding to the mix. OIE85Jy-13 | 0 |